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DOE OSTI2020

Materials Data on HfMg30CrO32 by Materials Project

Mg30HfCrO32 is Molybdenum Carbide MAX Phase-derived structured and crystallizes in the tetragonal P4/mmm space group. The structure is three-dimensional. there are eight inequivalent Mg sites. In the first Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with two equivalent MgO6 octahedra, corners with two equivalent HfO6 octahedra, corners with two equivalent CrO6 octahedra, and edges with twelve MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are a spread of Mg–O bond distances ranging from 1.99–2.23 Å. In the second Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with two equivalent CrO6 octahedra, corners with four equivalent MgO6 octahedra, and edges with twelve MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are two shorter (2.02 Å) and four longer (2.19 Å) Mg–O bond lengths. In the third Mg site, Mg is bonded to six O atoms to form a mixture of edge and corner-sharing MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are four shorter (2.13 Å) and two longer (2.18 Å) Mg–O bond lengths. In the fourth Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with two equivalent HfO6 octahedra, corners with four equivalent MgO6 octahedra, and edges with twelve MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are four shorter (2.14 Å) and two longer (2.20 Å) Mg–O bond lengths. In the fifth Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with six MgO6 octahedra, an edgeedge with one HfO6 octahedra, an edgeedge with one CrO6 octahedra, and edges with ten MgO6 octahedra. The corner-sharing octahedra tilt angles range from 4–13°. There are a spread of Mg–O bond distances ranging from 2.10–2.24 Å. In the sixth Mg site, Mg is bonded to six O atoms to form a mixture of edge and corner-sharing MgO6 octahedra. The corner-sharing octahedra tilt angles range from 2–4°. There are a spread of Mg–O bond distances ranging from 2.14–2.18 Å. In the seventh Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with six MgO6 octahedra, an edgeedge with one CrO6 octahedra, and edges with eleven MgO6 octahedra. The corner-sharing octahedra tilt angles range from 1–10°. There are a spread of Mg–O bond distances ranging from 2.14–2.18 Å. In the eighth Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with six MgO6 octahedra, an edgeedge with one HfO6 octahedra, and edges with eleven MgO6 octahedra. The corner-sharing octahedra tilt angles range from 2–7°. There are a spread of Mg–O bond distances ranging from 2.09–2.23 Å. Hf is bonded to six O atoms to form HfO6 octahedra that share corners with six MgO6 octahedra and edges with twelve MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are four shorter (2.09 Å) and two longer (2.11 Å) Hf–O bond lengths. Cr is bonded to six O atoms to form CrO6 octahedra that share corners with six MgO6 octahedra and edges with twelve MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are two shorter (2.29 Å) and four longer (2.33 Å) Cr–O bond lengths. There are eleven inequivalent O sites. In the first O site, O is bonded to five Mg and one Cr atom to form a mixture of edge and corner-sharing OMg5Cr octahedra. The corner-sharing octahedra tilt angles range from 0–4°. In the second O site, O is bonded to six Mg atoms to form OMg6 octahedra that share corners with six OMg5Cr octahedra and edges with twelve OMg6 octahedra. The corner-sharing octahedra tilt angles range from 0–4°. In the third O site, O is bonded to five Mg and one Hf atom to form a mixture of edge and corner-sharing OHfMg5 octahedra. The corner-sharing octahedra tilt angles range from 0–4°. In the fourth O site, O is bonded to six Mg atoms to form OMg6 octahedra that share corners with six OMg5Cr octahedra and edges with twelve OMg6 octahedra. The corner-sharing octahedra tilt angles range from 0–4°. There are two shorter (2.09 Å) and two longer (2.18 Å) O–Mg bond lengths. In the fifth O site, O is bonded to six Mg atoms to form OMg6 octahedra that share corners with six equivalent OMg6 octahedra and edges with twelve OMg5Cr octahedra. The corner-sharing octahedra tilt angles range from 2–6°. In the sixth O site, O is bonded to five Mg and one Cr atom to form a mixture of edge and corner-sharing OMg5Cr octahedra. The corner-sharing octahedra tilt angles range from 0–10°. In the seventh O site, O is bonded to five Mg and one Cr atom to form a mixture of edge and corner-sharing OMg5Cr octahedra. The corner-sharing octahedra tilt angles range from 0–10°. There are two shorter (2.10 Å) and two longer (2.17 Å) O–Mg bond lengths. In the eighth O site, O is bonded to five Mg and one Hf atom to form OHfMg5 octahedra that share corners with six OMg5Cr octahedra and edges with twelve OMg6 octahedra. The corner-sharing octahedra tilt angles range from 0–10°. In the ninth O site, O is bonded to six Mg atoms to form a mixture of edge and corner-sharing OMg6 octahedra. The corner-sharing octahedra tilt angles range from 0–6°. In the tenth O site, O is bonded to six Mg atoms to form OMg6 octahedra that share corners with six OHfMg5 octahedra and edges with twelve OMg6 octahedra. The corner-sharing octahedra tilt angles range from 0–6°. In the eleventh O site, O is bonded to six Mg atoms to form OMg6 octahedra that share corners with six OHfMg5 octahedra and edges with twelve OMg6 octahedra. The corner-sharing octahedra tilt angles range from 0–6°. There are two shorter (2.10 Å) and two longer (2.18 Å) O–Mg bond lengths.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on CaHfMg30O32 by Materials Project

CaMg30HfO32 is alpha Po-derived structured and crystallizes in the tetragonal P4/mmm space group. The structure is three-dimensional. Ca is bonded to six O atoms to form CaO6 octahedra that share corners with two equivalent HfO6 octahedra, corners with four equivalent MgO6 octahedra, and edges with twelve MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are two shorter (2.24 Å) and four longer (2.27 Å) Ca–O bond lengths. There are eight inequivalent Mg sites. In the first Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with two equivalent CaO6 octahedra, corners with four MgO6 octahedra, and edges with twelve MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are a spread of Mg–O bond distances ranging from 2.06–2.18 Å. In the second Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with two equivalent HfO6 octahedra, corners with four MgO6 octahedra, and edges with twelve MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are a spread of Mg–O bond distances ranging from 2.10–2.17 Å. In the third Mg site, Mg is bonded to six O atoms to form a mixture of edge and corner-sharing MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. All Mg–O bond lengths are 2.15 Å. In the fourth Mg site, Mg is bonded to six O atoms to form a mixture of edge and corner-sharing MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are two shorter (2.15 Å) and four longer (2.16 Å) Mg–O bond lengths. In the fifth Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with six MgO6 octahedra, an edgeedge with one CaO6 octahedra, an edgeedge with one HfO6 octahedra, and edges with ten MgO6 octahedra. The corner-sharing octahedra tilt angles range from 1–5°. There are a spread of Mg–O bond distances ranging from 2.08–2.25 Å. In the sixth Mg site, Mg is bonded to six O atoms to form a mixture of edge and corner-sharing MgO6 octahedra. The corner-sharing octahedra tilt angles range from 0–3°. There are a spread of Mg–O bond distances ranging from 2.15–2.18 Å. In the seventh Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with six MgO6 octahedra, an edgeedge with one CaO6 octahedra, and edges with eleven MgO6 octahedra. The corner-sharing octahedra tilt angles range from 1–3°. There are a spread of Mg–O bond distances ranging from 2.13–2.20 Å. In the eighth Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with six MgO6 octahedra, an edgeedge with one HfO6 octahedra, and edges with eleven MgO6 octahedra. The corner-sharing octahedra tilt angles range from 1–3°. There are a spread of Mg–O bond distances ranging from 2.13–2.20 Å. Hf is bonded to six O atoms to form HfO6 octahedra that share corners with two equivalent CaO6 octahedra, corners with four equivalent MgO6 octahedra, and edges with twelve MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are two shorter (2.06 Å) and four longer (2.23 Å) Hf–O bond lengths. There are sixteen inequivalent O sites. In the first O site, O is bonded to one Ca and five Mg atoms to form a mixture of edge and corner-sharing OCaMg5 octahedra. The corner-sharing octahedra tilt angles range from 0–1°. In the second O site, O is bonded to five Mg and one Hf atom to form OHfMg5 octahedra that share corners with six OCaMg5 octahedra and edges with twelve OHfMg5 octahedra. The corner-sharing octahedral tilt angles are 0°. In the third O site, O is bonded to six Mg atoms to form a mixture of edge and corner-sharing OMg6 octahedra. The corner-sharing octahedra tilt angles range from 0–1°. Both O–Mg bond lengths are 2.15 Å. In the fourth O site, O is bonded to six Mg atoms to form a mixture of edge and corner-sharing OMg6 octahedra. The corner-sharing octahedral tilt angles are 0°. Both O–Mg bond lengths are 2.15 Å. In the fifth O site, O is bonded to six Mg atoms to form a mixture of edge and corner-sharing OMg6 octahedra. The corner-sharing octahedra tilt angles range from 0–1°. There are two shorter (2.13 Å) and two longer (2.15 Å) O–Mg bond lengths. In the sixth O site, O is bonded to six Mg atoms to form a mixture of edge and corner-sharing OMg6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are two shorter (2.13 Å) and two longer (2.15 Å) O–Mg bond lengths. In the seventh O site, O is bonded to six Mg atoms to form OMg6 octahedra that share corners with six equivalent OMg6 octahedra and edges with twelve OCaMg5 octahedra. The corner-sharing octahedra tilt angles range from 1–5°. In the eighth O site, O is bonded to one Ca, four equivalent Mg, and one Hf atom to form OCaHfMg4 octahedra that share corners with six OCaHfMg4 octahedra and edges with twelve OCaMg5 octahedra. The corner-sharing octahedra tilt angles range from 0–3°. In the ninth O site, O is bonded to six Mg atoms to form OMg6 octahedra that share corners with six OCaHfMg4 octahedra and edges with twelve OCaMg5 octahedra. The corner-sharing octahedra tilt angles range from 0–3°. In the tenth O site, O is bonded to six Mg atoms to form OMg6 octahedra that share corners with six OCaHfMg4 octahedra and edges with twelve OCaMg5 octahedra. The corner-sharing octahedra tilt angles range from 0–3°. There are two shorter (2.08 Å) and two longer (2.18 Å) O–Mg bond lengths. In the eleventh O site, O is bonded to six Mg atoms to form a mixture of edge and corner-sharing OMg6 octahedra. The corner-sharing octahedral tilt angles are 0°. In the twelfth O site, O is bonded to six Mg atoms to form a mixture of edge and corner-sharing OMg6 octahedra. The corner-sharing octahedral tilt angles are 0°. All O–Mg bond lengths are 2.15 Å. In the thirteenth O site, O is bonded to one Ca and five Mg atoms to form a mixture of edge and corner-sharing OCaMg5 octahedra. The corner-sharing octahedra tilt angles range from 0–1°. There are two shorter (2.14 Å) and two longer (2.20 Å) O–Mg bond lengths. In the fourteenth O site, O is bonded to six Mg atoms to form a mixture of edge and corner-sharing OMg6 octahedra. The corner-sharing octahedra tilt angles range from 0–1°. The O–Mg bond length is 2.18 Å. In the fifteenth O site, O is bonded to six Mg atoms to form a mixture of edge and corner-sharing OMg6 octahedra. The corner-sharing octahedral tilt angles are 0°. The O–Mg bond length is 2.17 Å. In the sixteenth O site, O is bonded to six Mg atoms to form a mixture of edge and corner-sharing OMg6 octahedra. The corner-sharing octahedra tilt angles range from 0–1°. There are a spread of O–Mg bond distances ranging from 2.13–2.18 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on LaHfMg30O32 by Materials Project

Mg30LaHfO32 is alpha Po-derived structured and crystallizes in the tetragonal P4/mmm space group. The structure is three-dimensional. there are eight inequivalent Mg sites. In the first Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with two equivalent MgO6 octahedra, corners with two equivalent LaO6 octahedra, corners with two equivalent HfO6 octahedra, and edges with twelve MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are a spread of Mg–O bond distances ranging from 2.03–2.21 Å. In the second Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with two equivalent LaO6 octahedra, corners with four equivalent MgO6 octahedra, and edges with twelve MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are two shorter (2.02 Å) and four longer (2.21 Å) Mg–O bond lengths. In the third Mg site, Mg is bonded to six O atoms to form a mixture of edge and corner-sharing MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are a spread of Mg–O bond distances ranging from 2.13–2.20 Å. In the fourth Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with two equivalent HfO6 octahedra, corners with four equivalent MgO6 octahedra, and edges with twelve MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are four shorter (2.17 Å) and two longer (2.19 Å) Mg–O bond lengths. In the fifth Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with six MgO6 octahedra, an edgeedge with one LaO6 octahedra, an edgeedge with one HfO6 octahedra, and edges with ten MgO6 octahedra. The corner-sharing octahedra tilt angles range from 2–6°. There are a spread of Mg–O bond distances ranging from 2.13–2.24 Å. In the sixth Mg site, Mg is bonded to six O atoms to form a mixture of edge and corner-sharing MgO6 octahedra. The corner-sharing octahedra tilt angles range from 1–2°. There are a spread of Mg–O bond distances ranging from 2.17–2.19 Å. In the seventh Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with six MgO6 octahedra, an edgeedge with one LaO6 octahedra, and edges with eleven MgO6 octahedra. The corner-sharing octahedra tilt angles range from 2–4°. There are a spread of Mg–O bond distances ranging from 2.09–2.25 Å. In the eighth Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with six MgO6 octahedra, an edgeedge with one HfO6 octahedra, and edges with eleven MgO6 octahedra. The corner-sharing octahedra tilt angles range from 0–3°. There are a spread of Mg–O bond distances ranging from 2.13–2.22 Å. La is bonded to six O atoms to form LaO6 octahedra that share corners with six MgO6 octahedra and edges with twelve MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. All La–O bond lengths are 2.33 Å. Hf is bonded to six O atoms to form HfO6 octahedra that share corners with six MgO6 octahedra and edges with twelve MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are two shorter (2.16 Å) and four longer (2.24 Å) Hf–O bond lengths. There are eleven inequivalent O sites. In the first O site, O is bonded to five Mg and one La atom to form OLaMg5 octahedra that share corners with six OLaMg5 octahedra and edges with twelve OMg6 octahedra. The corner-sharing octahedra tilt angles range from 0–1°. In the second O site, O is bonded to six Mg atoms to form OMg6 octahedra that share corners with six OLaMg5 octahedra and edges with twelve OMg6 octahedra. The corner-sharing octahedra tilt angles range from 0–2°. In the third O site, O is bonded to five Mg and one Hf atom to form a mixture of edge and corner-sharing OHfMg5 octahedra. The corner-sharing octahedra tilt angles range from 0–2°. In the fourth O site, O is bonded to six Mg atoms to form OMg6 octahedra that share corners with six equivalent OMg6 octahedra and edges with twelve OLaMg5 octahedra. The corner-sharing octahedra tilt angles range from 1–6°. In the fifth O site, O is bonded to five Mg and one La atom to form a mixture of edge and corner-sharing OLaMg5 octahedra. The corner-sharing octahedra tilt angles range from 0–1°. In the sixth O site, O is bonded to five Mg and one La atom to form a mixture of edge and corner-sharing OLaMg5 octahedra. The corner-sharing octahedra tilt angles range from 0–1°. There are two shorter (2.24 Å) and two longer (2.25 Å) O–Mg bond lengths. In the seventh O site, O is bonded to five Mg and one Hf atom to form OHfMg5 octahedra that share corners with six OLaMg5 octahedra and edges with twelve OMg6 octahedra. The corner-sharing octahedra tilt angles range from 0–1°. In the eighth O site, O is bonded to six Mg atoms to form a mixture of edge and corner-sharing OMg6 octahedra. The corner-sharing octahedra tilt angles range from 0–1°. In the ninth O site, O is bonded to six Mg atoms to form a mixture of edge and corner-sharing OMg6 octahedra. The corner-sharing octahedra tilt angles range from 0–1°. There are two shorter (2.09 Å) and two longer (2.19 Å) O–Mg bond lengths. In the tenth O site, O is bonded to six Mg atoms to form OMg6 octahedra that share corners with six OHfMg5 octahedra and edges with twelve OMg6 octahedra. The corner-sharing octahedra tilt angles range from 0–1°. In the eleventh O site, O is bonded to six Mg atoms to form OMg6 octahedra that share corners with six OHfMg5 octahedra and edges with twelve OMg6 octahedra. The corner-sharing octahedra tilt angles range from 0–1°. There are two shorter (2.13 Å) and two longer (2.18 Å) O–Mg bond lengths.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on YHfMg30O32 by Materials Project

Mg30YHfO32 is alpha Po-derived structured and crystallizes in the tetragonal P4/mmm space group. The structure is three-dimensional. there are eight inequivalent Mg sites. In the first Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with two equivalent MgO6 octahedra, corners with two equivalent YO6 octahedra, corners with two equivalent HfO6 octahedra, and edges with twelve MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are four shorter (2.10 Å) and two longer (2.18 Å) Mg–O bond lengths. In the second Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with two equivalent YO6 octahedra, corners with four equivalent MgO6 octahedra, and edges with twelve MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are two shorter (2.08 Å) and four longer (2.18 Å) Mg–O bond lengths. In the third Mg site, Mg is bonded to six O atoms to form a mixture of edge and corner-sharing MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are a spread of Mg–O bond distances ranging from 2.14–2.18 Å. In the fourth Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with two equivalent HfO6 octahedra, corners with four equivalent MgO6 octahedra, and edges with twelve MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are four shorter (2.16 Å) and two longer (2.17 Å) Mg–O bond lengths. In the fifth Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with six MgO6 octahedra, an edgeedge with one YO6 octahedra, an edgeedge with one HfO6 octahedra, and edges with ten MgO6 octahedra. The corner-sharing octahedra tilt angles range from 1–5°. There are a spread of Mg–O bond distances ranging from 2.14–2.20 Å. In the sixth Mg site, Mg is bonded to six O atoms to form a mixture of edge and corner-sharing MgO6 octahedra. The corner-sharing octahedra tilt angles range from 0–1°. There are two shorter (2.16 Å) and four longer (2.17 Å) Mg–O bond lengths. In the seventh Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with six MgO6 octahedra, an edgeedge with one YO6 octahedra, and edges with eleven MgO6 octahedra. The corner-sharing octahedra tilt angles range from 1–3°. There are a spread of Mg–O bond distances ranging from 2.10–2.22 Å. In the eighth Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with six MgO6 octahedra, an edgeedge with one HfO6 octahedra, and edges with eleven MgO6 octahedra. The corner-sharing octahedra tilt angles range from 1–3°. There are a spread of Mg–O bond distances ranging from 2.12–2.21 Å. Y is bonded to six O atoms to form YO6 octahedra that share corners with six MgO6 octahedra and edges with twelve MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. All Y–O bond lengths are 2.24 Å. Hf is bonded to six O atoms to form HfO6 octahedra that share corners with six MgO6 octahedra and edges with twelve MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are two shorter (2.15 Å) and four longer (2.24 Å) Hf–O bond lengths. There are ten inequivalent O sites. In the first O site, O is bonded to five Mg and one Y atom to form OYMg5 octahedra that share corners with six OYMg5 octahedra and edges with twelve OMg6 octahedra. The corner-sharing octahedral tilt angles are 0°. In the second O site, O is bonded to six Mg atoms to form OMg6 octahedra that share corners with six OYMg5 octahedra and edges with twelve OMg6 octahedra. The corner-sharing octahedra tilt angles range from 0–2°. In the third O site, O is bonded to five Mg and one Hf atom to form a mixture of edge and corner-sharing OHfMg5 octahedra. The corner-sharing octahedra tilt angles range from 0–2°. In the fourth O site, O is bonded to six Mg atoms to form OMg6 octahedra that share corners with six equivalent OMg6 octahedra and edges with twelve OYMg5 octahedra. The corner-sharing octahedra tilt angles range from 0–4°. In the fifth O site, O is bonded to five Mg and one Y atom to form a mixture of edge and corner-sharing OYMg5 octahedra. The corner-sharing octahedra tilt angles range from 0–2°. In the sixth O site, O is bonded to five Mg and one Y atom to form a mixture of edge and corner-sharing OYMg5 octahedra. The corner-sharing octahedra tilt angles range from 0–2°. There are two shorter (2.20 Å) and two longer (2.22 Å) O–Mg bond lengths. In the seventh O site, O is bonded to five Mg and one Hf atom to form OHfMg5 octahedra that share corners with six OYMg5 octahedra and edges with twelve OMg6 octahedra. The corner-sharing octahedra tilt angles range from 0–2°. In the eighth O site, O is bonded to six Mg atoms to form a mixture of edge and corner-sharing OMg6 octahedra. The corner-sharing octahedral tilt angles are 0°. In the ninth O site, O is bonded to six Mg atoms to form a mixture of edge and corner-sharing OMg6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are two shorter (2.10 Å) and two longer (2.17 Å) O–Mg bond lengths. In the tenth O site, O is bonded to six Mg atoms to form OMg6 octahedra that share corners with six OHfMg5 octahedra and edges with twelve OMg6 octahedra. The corner-sharing octahedra tilt angles range from 0–1°.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on HfMg30SbO32 by Materials Project

Mg30HfSbO32 is Caswellsilverite-derived structured and crystallizes in the tetragonal P4/mmm space group. The structure is three-dimensional. there are eight inequivalent Mg sites. In the first Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with two equivalent MgO6 octahedra, corners with two equivalent HfO6 octahedra, corners with two equivalent SbO6 octahedra, and edges with twelve MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are a spread of Mg–O bond distances ranging from 1.86–2.27 Å. In the second Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with two equivalent SbO6 octahedra, corners with four equivalent MgO6 octahedra, and edges with twelve MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are two shorter (1.89 Å) and four longer (2.24 Å) Mg–O bond lengths. In the third Mg site, Mg is bonded to six O atoms to form a mixture of edge and corner-sharing MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are a spread of Mg–O bond distances ranging from 2.10–2.22 Å. In the fourth Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with two equivalent HfO6 octahedra, corners with four equivalent MgO6 octahedra, and edges with twelve MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are four shorter (2.14 Å) and two longer (2.21 Å) Mg–O bond lengths. In the fifth Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with six MgO6 octahedra, an edgeedge with one HfO6 octahedra, an edgeedge with one SbO6 octahedra, and edges with ten MgO6 octahedra. The corner-sharing octahedra tilt angles range from 4–20°. There are a spread of Mg–O bond distances ranging from 2.15–2.25 Å. In the sixth Mg site, Mg is bonded to six O atoms to form a mixture of edge and corner-sharing MgO6 octahedra. The corner-sharing octahedra tilt angles range from 3–4°. There are a spread of Mg–O bond distances ranging from 2.16–2.19 Å. In the seventh Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with six MgO6 octahedra, an edgeedge with one SbO6 octahedra, and edges with eleven MgO6 octahedra. The corner-sharing octahedra tilt angles range from 2–17°. There are a spread of Mg–O bond distances ranging from 2.14–2.21 Å. In the eighth Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with six MgO6 octahedra, an edgeedge with one HfO6 octahedra, and edges with eleven MgO6 octahedra. The corner-sharing octahedra tilt angles range from 0–8°. There are a spread of Mg–O bond distances ranging from 2.11–2.25 Å. Hf is bonded to six O atoms to form HfO6 octahedra that share corners with six MgO6 octahedra and edges with twelve MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are four shorter (2.09 Å) and two longer (2.11 Å) Hf–O bond lengths. Sb is bonded to six O atoms to form SbO6 octahedra that share corners with six MgO6 octahedra and edges with twelve MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are two shorter (2.44 Å) and four longer (2.49 Å) Sb–O bond lengths. There are eight inequivalent O sites. In the first O site, O is bonded to five Mg and one Sb atom to form distorted OMg5Sb octahedra that share corners with six OMg5Sb octahedra and edges with eight OMg6 octahedra. The corner-sharing octahedra tilt angles range from 0–8°. In the second O site, O is bonded to six Mg atoms to form OMg6 octahedra that share corners with six OMg5Sb octahedra and edges with ten OMg6 octahedra. The corner-sharing octahedra tilt angles range from 0–8°. In the third O site, O is bonded to five Mg and one Hf atom to form a mixture of edge and corner-sharing OHfMg5 octahedra. The corner-sharing octahedra tilt angles range from 0–3°. In the fourth O site, O is bonded to six Mg atoms to form OMg6 octahedra that share corners with six equivalent OMg6 octahedra and edges with ten OMg5Sb octahedra. The corner-sharing octahedra tilt angles range from 2–6°. In the fifth O site, O is bonded in a 6-coordinate geometry to five Mg and one Sb atom. In the sixth O site, O is bonded to five Mg and one Hf atom to form OHfMg5 octahedra that share corners with four OHfMg5 octahedra and edges with ten OMg6 octahedra. The corner-sharing octahedra tilt angles range from 0–7°. In the seventh O site, O is bonded to six Mg atoms to form OMg6 octahedra that share corners with four OMg6 octahedra and edges with twelve OMg5Sb octahedra. The corner-sharing octahedra tilt angles range from 0–3°. In the eighth O site, O is bonded to six Mg atoms to form OMg6 octahedra that share corners with six OHfMg5 octahedra and edges with twelve OMg6 octahedra. The corner-sharing octahedra tilt angles range from 0–7°.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on HfTaB2 by Materials Project

HfTaB2 is delta Molybdenum Boride-derived structured and crystallizes in the monoclinic Pm space group. The structure is three-dimensional. Hf is bonded in a 7-coordinate geometry to seven B atoms. There are a spread of Hf–B bond distances ranging from 2.48–2.67 Å. Ta is bonded in a 7-coordinate geometry to seven B atoms. There are a spread of Ta–B bond distances ranging from 2.42–2.81 Å. There are two inequivalent B sites. In the first B site, B is bonded in a 9-coordinate geometry to three equivalent Hf, four equivalent Ta, and two equivalent B atoms. Both B–B bond lengths are 1.86 Å. In the second B site, B is bonded in a 9-coordinate geometry to four equivalent Hf, three equivalent Ta, and two equivalent B atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on CaHfMg14O16 by Materials Project

CaMg14HfO16 is alpha Po-derived structured and crystallizes in the tetragonal P4/mmm space group. The structure is three-dimensional. Ca is bonded to six O atoms to form CaO6 octahedra that share corners with two equivalent CaO6 octahedra, corners with four equivalent MgO6 octahedra, and edges with twelve MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are two shorter (2.20 Å) and four longer (2.29 Å) Ca–O bond lengths. There are five inequivalent Mg sites. In the first Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with two equivalent CaO6 octahedra, corners with two equivalent MgO6 octahedra, corners with two equivalent HfO6 octahedra, and edges with twelve MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are a spread of Mg–O bond distances ranging from 2.06–2.20 Å. In the second Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with six MgO6 octahedra, edges with two equivalent CaO6 octahedra, and edges with ten MgO6 octahedra. The corner-sharing octahedra tilt angles range from 0–4°. There are a spread of Mg–O bond distances ranging from 2.14–2.22 Å. In the third Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with six MgO6 octahedra, edges with two equivalent CaO6 octahedra, and edges with ten MgO6 octahedra. The corner-sharing octahedra tilt angles range from 0–4°. There are a spread of Mg–O bond distances ranging from 2.14–2.22 Å. In the fourth Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with six MgO6 octahedra, edges with two equivalent HfO6 octahedra, and edges with ten MgO6 octahedra. The corner-sharing octahedra tilt angles range from 0–2°. There are a spread of Mg–O bond distances ranging from 2.13–2.23 Å. In the fifth Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with six equivalent MgO6 octahedra, an edgeedge with one CaO6 octahedra, an edgeedge with one HfO6 octahedra, and edges with ten MgO6 octahedra. The corner-sharing octahedra tilt angles range from 0–7°. There are two shorter (2.16 Å) and four longer (2.20 Å) Mg–O bond lengths. Hf is bonded to six O atoms to form HfO6 octahedra that share corners with two equivalent HfO6 octahedra, corners with four equivalent MgO6 octahedra, and edges with twelve MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are four shorter (2.19 Å) and two longer (2.20 Å) Hf–O bond lengths. There are seven inequivalent O sites. In the first O site, O is bonded to one Ca and five Mg atoms to form a mixture of edge and corner-sharing OCaMg5 octahedra. The corner-sharing octahedra tilt angles range from 0–4°. In the second O site, O is bonded to five Mg and one Hf atom to form a mixture of edge and corner-sharing OHfMg5 octahedra. The corner-sharing octahedra tilt angles range from 0–4°. In the third O site, O is bonded to six Mg atoms to form OMg6 octahedra that share corners with six equivalent OMg6 octahedra and edges with twelve OCaMg5 octahedra. The corner-sharing octahedra tilt angles range from 1–3°. In the fourth O site, O is bonded to two equivalent Ca and four Mg atoms to form OCa2Mg4 octahedra that share corners with six OCa2Mg4 octahedra and edges with twelve OCaMg5 octahedra. The corner-sharing octahedral tilt angles are 0°. In the fifth O site, O is bonded to six Mg atoms to form OMg6 octahedra that share corners with six OCa2Mg4 octahedra and edges with twelve OCaMg5 octahedra. The corner-sharing octahedral tilt angles are 0°. In the sixth O site, O is bonded to four equivalent Mg and two equivalent Hf atoms to form OHf2Mg4 octahedra that share corners with six OMg6 octahedra and edges with twelve OHfMg5 octahedra. The corner-sharing octahedral tilt angles are 0°. In the seventh O site, O is bonded to one Ca and five Mg atoms to form a mixture of edge and corner-sharing OCaMg5 octahedra. The corner-sharing octahedra tilt angles range from 0–4°. Both O–Mg bond lengths are 2.16 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on HfMg30SiO32 by Materials Project

Mg30HfSiO32 is alpha Po-derived structured and crystallizes in the tetragonal P4/mmm space group. The structure is three-dimensional. there are eight inequivalent Mg sites. In the first Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with two equivalent SiO6 octahedra, corners with four MgO6 octahedra, and edges with twelve MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are two shorter (2.00 Å) and four longer (2.18 Å) Mg–O bond lengths. In the second Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with two equivalent HfO6 octahedra, corners with four MgO6 octahedra, and edges with twelve MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are a spread of Mg–O bond distances ranging from 2.12–2.17 Å. In the third Mg site, Mg is bonded to six O atoms to form a mixture of corner and edge-sharing MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are four shorter (2.14 Å) and two longer (2.17 Å) Mg–O bond lengths. In the fourth Mg site, Mg is bonded to six O atoms to form a mixture of corner and edge-sharing MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are two shorter (2.14 Å) and four longer (2.16 Å) Mg–O bond lengths. In the fifth Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with six MgO6 octahedra, an edgeedge with one HfO6 octahedra, an edgeedge with one SiO6 octahedra, and edges with ten MgO6 octahedra. The corner-sharing octahedra tilt angles range from 3–6°. There are a spread of Mg–O bond distances ranging from 2.10–2.22 Å. In the sixth Mg site, Mg is bonded to six O atoms to form a mixture of corner and edge-sharing MgO6 octahedra. The corner-sharing octahedra tilt angles range from 1–3°. There are a spread of Mg–O bond distances ranging from 2.14–2.17 Å. In the seventh Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with six MgO6 octahedra, an edgeedge with one SiO6 octahedra, and edges with eleven MgO6 octahedra. The corner-sharing octahedra tilt angles range from 0–7°. There are a spread of Mg–O bond distances ranging from 2.14–2.18 Å. In the eighth Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with six MgO6 octahedra, an edgeedge with one HfO6 octahedra, and edges with eleven MgO6 octahedra. The corner-sharing octahedral tilt angles are 3°. There are a spread of Mg–O bond distances ranging from 2.11–2.21 Å. Hf is bonded to six O atoms to form HfO6 octahedra that share corners with two equivalent SiO6 octahedra, corners with four equivalent MgO6 octahedra, and edges with twelve MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are two shorter (2.11 Å) and four longer (2.15 Å) Hf–O bond lengths. Si is bonded to six O atoms to form SiO6 octahedra that share corners with two equivalent HfO6 octahedra, corners with four equivalent MgO6 octahedra, and edges with twelve MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are two shorter (2.20 Å) and four longer (2.32 Å) Si–O bond lengths. There are eleven inequivalent O sites. In the first O site, O is bonded to five Mg and one Si atom to form a mixture of corner and edge-sharing OMg5Si octahedra. The corner-sharing octahedra tilt angles range from 0–4°. In the second O site, O is bonded to five Mg and one Hf atom to form OHfMg5 octahedra that share corners with six OMg5Si octahedra and edges with twelve OHfMg5 octahedra. The corner-sharing octahedra tilt angles range from 0–3°. In the third O site, O is bonded to six Mg atoms to form a mixture of corner and edge-sharing OMg6 octahedra. The corner-sharing octahedra tilt angles range from 0–4°. In the fourth O site, O is bonded to six Mg atoms to form a mixture of corner and edge-sharing OMg6 octahedra. The corner-sharing octahedra tilt angles range from 0–3°. Both O–Mg bond lengths are 2.16 Å. In the fifth O site, O is bonded to six Mg atoms to form a mixture of corner and edge-sharing OMg6 octahedra. The corner-sharing octahedra tilt angles range from 0–3°. There are two shorter (2.11 Å) and two longer (2.16 Å) O–Mg bond lengths. In the sixth O site, O is bonded to six Mg atoms to form OMg6 octahedra that share corners with six equivalent OMg6 octahedra and edges with twelve OMg5Si octahedra. The corner-sharing octahedra tilt angles range from 1–4°. In the seventh O site, O is bonded to four equivalent Mg, one Hf, and one Si atom to form OHfMg4Si octahedra that share corners with six OHfMg4Si octahedra and edges with twelve OMg5Si octahedra. The corner-sharing octahedra tilt angles range from 0–5°. In the eighth O site, O is bonded to six Mg atoms to form OMg6 octahedra that share corners with six OHfMg4Si octahedra and edges with twelve OMg5Si octahedra. The corner-sharing octahedra tilt angles range from 0–5°. In the ninth O site, O is bonded to six Mg atoms to form a mixture of corner and edge-sharing OMg6 octahedra. The corner-sharing octahedra tilt angles range from 0–2°. In the tenth O site, O is bonded to five Mg and one Si atom to form a mixture of corner and edge-sharing OMg5Si octahedra. The corner-sharing octahedra tilt angles range from 0–4°. There are two shorter (2.10 Å) and two longer (2.18 Å) O–Mg bond lengths. In the eleventh O site, O is bonded to six Mg atoms to form a mixture of corner and edge-sharing OMg6 octahedra. The corner-sharing octahedra tilt angles range from 0–3°. The O–Mg bond length is 2.16 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on HfMg by Materials Project

Mg(Hf) is Halite, Rock Salt structured and crystallizes in the cubic Fm-3m space group. The structure is three-dimensional. Mg is bonded to six equivalent Hf atoms to form a mixture of edge and corner-sharing MgHf6 octahedra. The corner-sharing octahedral tilt angles are 0°. All Mg–Hf bond lengths are 2.86 Å. Hf is bonded to six equivalent Mg atoms to form a mixture of edge and corner-sharing HfMg6 octahedra. The corner-sharing octahedral tilt angles are 0°.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on HfMg30WO32 by Materials Project

Mg30HfWO32 is Molybdenum Carbide MAX Phase-derived structured and crystallizes in the tetragonal P4/mmm space group. The structure is three-dimensional. there are eight inequivalent Mg sites. In the first Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with two equivalent WO6 octahedra, corners with four MgO6 octahedra, and edges with twelve MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are a spread of Mg–O bond distances ranging from 2.00–2.19 Å. In the second Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with two equivalent HfO6 octahedra, corners with four MgO6 octahedra, and edges with twelve MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are a spread of Mg–O bond distances ranging from 2.13–2.17 Å. In the third Mg site, Mg is bonded to six O atoms to form a mixture of edge and corner-sharing MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are four shorter (2.14 Å) and two longer (2.17 Å) Mg–O bond lengths. In the fourth Mg site, Mg is bonded to six O atoms to form a mixture of edge and corner-sharing MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are two shorter (2.15 Å) and four longer (2.16 Å) Mg–O bond lengths. In the fifth Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with six MgO6 octahedra, an edgeedge with one HfO6 octahedra, an edgeedge with one WO6 octahedra, and edges with ten MgO6 octahedra. The corner-sharing octahedra tilt angles range from 3–11°. There are a spread of Mg–O bond distances ranging from 2.09–2.23 Å. In the sixth Mg site, Mg is bonded to six O atoms to form a mixture of edge and corner-sharing MgO6 octahedra. The corner-sharing octahedra tilt angles range from 0–3°. There are a spread of Mg–O bond distances ranging from 2.15–2.17 Å. In the seventh Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with six MgO6 octahedra, an edgeedge with one WO6 octahedra, and edges with eleven MgO6 octahedra. The corner-sharing octahedra tilt angles range from 0–7°. There are two shorter (2.14 Å) and four longer (2.17 Å) Mg–O bond lengths. In the eighth Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with six MgO6 octahedra, an edgeedge with one HfO6 octahedra, and edges with eleven MgO6 octahedra. The corner-sharing octahedra tilt angles range from 3–4°. There are a spread of Mg–O bond distances ranging from 2.10–2.20 Å. Hf is bonded to six O atoms to form HfO6 octahedra that share corners with two equivalent WO6 octahedra, corners with four equivalent MgO6 octahedra, and edges with twelve MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are two shorter (2.02 Å) and four longer (2.13 Å) Hf–O bond lengths. W is bonded to six O atoms to form WO6 octahedra that share corners with two equivalent HfO6 octahedra, corners with four equivalent MgO6 octahedra, and edges with twelve MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. All W–O bond lengths are 2.30 Å. There are eleven inequivalent O sites. In the first O site, O is bonded to five Mg and one W atom to form OMg5W octahedra that share corners with six OHfMg5 octahedra and edges with twelve OMg5W octahedra. The corner-sharing octahedra tilt angles range from 0–4°. In the second O site, O is bonded to five Mg and one Hf atom to form OHfMg5 octahedra that share corners with six OMg5W octahedra and edges with twelve OHfMg5 octahedra. The corner-sharing octahedra tilt angles range from 0–3°. In the third O site, O is bonded to six Mg atoms to form a mixture of edge and corner-sharing OMg6 octahedra. The corner-sharing octahedra tilt angles range from 0–4°. In the fourth O site, O is bonded to six Mg atoms to form a mixture of edge and corner-sharing OMg6 octahedra. The corner-sharing octahedra tilt angles range from 0–3°. Both O–Mg bond lengths are 2.17 Å. In the fifth O site, O is bonded to five Mg and one W atom to form a mixture of edge and corner-sharing OMg5W octahedra. The corner-sharing octahedra tilt angles range from 0–4°. There are a spread of O–Mg bond distances ranging from 2.00–2.17 Å. In the sixth O site, O is bonded to six Mg atoms to form a mixture of edge and corner-sharing OMg6 octahedra. The corner-sharing octahedra tilt angles range from 0–3°. There are two shorter (2.10 Å) and two longer (2.17 Å) O–Mg bond lengths. In the seventh O site, O is bonded to six Mg atoms to form OMg6 octahedra that share corners with six equivalent OMg6 octahedra and edges with twelve OMg5W octahedra. The corner-sharing octahedra tilt angles range from 1–5°. In the eighth O site, O is bonded to four equivalent Mg, one Hf, and one W atom to form OHfMg4W octahedra that share corners with six OHfMg4W octahedra and edges with twelve OMg5W octahedra. The corner-sharing octahedra tilt angles range from 0–8°. In the ninth O site, O is bonded to six Mg atoms to form OMg6 octahedra that share corners with six OHfMg4W octahedra and edges with twelve OMg5W octahedra. The corner-sharing octahedra tilt angles range from 0–8°. In the tenth O site, O is bonded to six Mg atoms to form a mixture of edge and corner-sharing OMg6 octahedra. The corner-sharing octahedra tilt angles range from 0–2°. In the eleventh O site, O is bonded to six Mg atoms to form a mixture of edge and corner-sharing OMg6 octahedra. The corner-sharing octahedra tilt angles range from 0–3°. The O–Mg bond length is 2.15 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on HfMg30BO32 by Materials Project

Mg30HfO32B is Molybdenum Carbide MAX Phase-derived structured and crystallizes in the tetragonal P4/mmm space group. The structure is three-dimensional and consists of one boron molecule and one Mg30HfO32 framework. In the Mg30HfO32 framework, there are eight inequivalent Mg sites. In the first Mg site, Mg is bonded to six O atoms to form a mixture of edge and corner-sharing MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are a spread of Mg–O bond distances ranging from 2.01–2.18 Å. In the second Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with two equivalent HfO6 octahedra, corners with four MgO6 octahedra, and edges with twelve MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are a spread of Mg–O bond distances ranging from 2.12–2.15 Å. In the third Mg site, Mg is bonded to six O atoms to form a mixture of edge and corner-sharing MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are four shorter (2.13 Å) and two longer (2.16 Å) Mg–O bond lengths. In the fourth Mg site, Mg is bonded to six O atoms to form a mixture of edge and corner-sharing MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are two shorter (2.14 Å) and four longer (2.15 Å) Mg–O bond lengths. In the fifth Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with six MgO6 octahedra, an edgeedge with one HfO6 octahedra, and edges with ten MgO6 octahedra. The corner-sharing octahedra tilt angles range from 1–10°. There are a spread of Mg–O bond distances ranging from 2.07–2.23 Å. In the sixth Mg site, Mg is bonded to six O atoms to form a mixture of edge and corner-sharing MgO6 octahedra. The corner-sharing octahedra tilt angles range from 0–3°. There are a spread of Mg–O bond distances ranging from 2.13–2.17 Å. In the seventh Mg site, Mg is bonded to six O atoms to form a mixture of edge and corner-sharing MgO6 octahedra. The corner-sharing octahedra tilt angles range from 1–8°. There are a spread of Mg–O bond distances ranging from 2.14–2.16 Å. In the eighth Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with six MgO6 octahedra, an edgeedge with one HfO6 octahedra, and edges with eleven MgO6 octahedra. The corner-sharing octahedra tilt angles range from 1–2°. There are a spread of Mg–O bond distances ranging from 2.11–2.19 Å. Hf is bonded to six O atoms to form HfO6 octahedra that share corners with four equivalent MgO6 octahedra and edges with twelve MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are two shorter (2.04 Å) and four longer (2.16 Å) Hf–O bond lengths. There are eight inequivalent O sites. In the first O site, O is bonded to five Mg atoms to form OMg5 square pyramids that share corners with four OHfMg5 octahedra, corners with five OMg5 square pyramids, and edges with eight OMg6 octahedra. The corner-sharing octahedra tilt angles range from 2–5°. In the second O site, O is bonded to five Mg and one Hf atom to form OHfMg5 octahedra that share corners with four OHfMg5 octahedra, corners with two equivalent OMg5 square pyramids, edges with ten OHfMg5 octahedra, and edges with two equivalent OHfMg4 square pyramids. The corner-sharing octahedra tilt angles range from 0–2°. In the third O site, O is bonded to six Mg atoms to form OMg6 octahedra that share corners with four OMg6 octahedra, corners with two equivalent OMg5 square pyramids, edges with ten OMg6 octahedra, and edges with two equivalent OMg5 square pyramids. The corner-sharing octahedral tilt angles are 0°. In the fourth O site, O is bonded to six Mg atoms to form a mixture of edge and corner-sharing OMg6 octahedra. The corner-sharing octahedra tilt angles range from 0–2°. In the fifth O site, O is bonded to six Mg atoms to form OMg6 octahedra that share corners with six equivalent OMg6 octahedra, edges with nine OHfMg5 octahedra, and edges with three OMg5 square pyramids. The corner-sharing octahedra tilt angles range from 0–5°. In the sixth O site, O is bonded to four equivalent Mg and one Hf atom to form distorted OHfMg4 square pyramids that share corners with four equivalent OMg6 octahedra, corners with five OHfMg4 square pyramids, and edges with eight OMg6 octahedra. The corner-sharing octahedral tilt angles are 8°. In the seventh O site, O is bonded to six Mg atoms to form OMg6 octahedra that share corners with four OMg6 octahedra, corners with two equivalent OHfMg4 square pyramids, edges with ten OHfMg5 octahedra, and edges with two equivalent OMg5 square pyramids. The corner-sharing octahedra tilt angles range from 0–2°. In the eighth O site, O is bonded to six Mg atoms to form a mixture of edge and corner-sharing OMg6 octahedra. The corner-sharing octahedra tilt angles range from 0–2°.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Hf4GeSb7 by Materials Project

Hf4GeSb7 crystallizes in the monoclinic Pm space group. The structure is three-dimensional. there are four inequivalent Hf4+ sites. In the first Hf4+ site, Hf4+ is bonded in a 8-coordinate geometry to eight Sb+2.86- atoms. There are a spread of Hf–Sb bond distances ranging from 2.93–3.18 Å. In the second Hf4+ site, Hf4+ is bonded in a 8-coordinate geometry to eight Sb+2.86- atoms. There are a spread of Hf–Sb bond distances ranging from 3.00–3.30 Å. In the third Hf4+ site, Hf4+ is bonded in a 7-coordinate geometry to seven Sb+2.86- atoms. There are a spread of Hf–Sb bond distances ranging from 2.95–3.10 Å. In the fourth Hf4+ site, Hf4+ is bonded in a 9-coordinate geometry to nine Sb+2.86- atoms. There are a spread of Hf–Sb bond distances ranging from 2.97–3.29 Å. Ge4+ is bonded in a distorted rectangular see-saw-like geometry to four Sb+2.86- atoms. There are two shorter (2.81 Å) and two longer (3.06 Å) Ge–Sb bond lengths. There are seven inequivalent Sb+2.86- sites. In the first Sb+2.86- site, Sb+2.86- is bonded in a 7-coordinate geometry to five Hf4+ and two equivalent Sb+2.86- atoms. Both Sb–Sb bond lengths are 3.14 Å. In the second Sb+2.86- site, Sb+2.86- is bonded in a 5-coordinate geometry to five Hf4+ atoms. In the third Sb+2.86- site, Sb+2.86- is bonded in a 7-coordinate geometry to five Hf4+ and two equivalent Sb+2.86- atoms. Both Sb–Sb bond lengths are 3.15 Å. In the fourth Sb+2.86- site, Sb+2.86- is bonded in a 7-coordinate geometry to five Hf4+ and two equivalent Ge4+ atoms. In the fifth Sb+2.86- site, Sb+2.86- is bonded in a 8-coordinate geometry to four Hf4+ and four Sb+2.86- atoms. Both Sb–Sb bond lengths are 2.93 Å. In the sixth Sb+2.86- site, Sb+2.86- is bonded in a 6-coordinate geometry to four Hf4+ and two equivalent Ge4+ atoms. In the seventh Sb+2.86- site, Sb+2.86- is bonded in a 8-coordinate geometry to four Hf4+ and four Sb+2.86- atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on HfMg14MnO16 by Materials Project

Mg14HfMnO16 is alpha Po-derived structured and crystallizes in the tetragonal P4/mmm space group. The structure is three-dimensional. there are six inequivalent Mg sites. In the first Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with two equivalent MgO6 octahedra, corners with two equivalent HfO6 octahedra, corners with two equivalent MnO6 octahedra, and edges with twelve MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are a spread of Mg–O bond distances ranging from 2.10–2.16 Å. In the second Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with six MgO6 octahedra, edges with two equivalent MnO6 octahedra, and edges with ten MgO6 octahedra. The corner-sharing octahedra tilt angles range from 0–3°. There are five shorter (2.16 Å) and one longer (2.18 Å) Mg–O bond lengths. In the third Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with six MgO6 octahedra, edges with two equivalent MnO6 octahedra, and edges with ten MgO6 octahedra. The corner-sharing octahedra tilt angles range from 0–3°. There are five shorter (2.16 Å) and one longer (2.18 Å) Mg–O bond lengths. In the fourth Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with six MgO6 octahedra, edges with two equivalent HfO6 octahedra, and edges with ten MgO6 octahedra. The corner-sharing octahedra tilt angles range from 0–1°. There are a spread of Mg–O bond distances ranging from 2.12–2.22 Å. In the fifth Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with six MgO6 octahedra, edges with two equivalent MnO6 octahedra, and edges with ten MgO6 octahedra. The corner-sharing octahedra tilt angles range from 0–3°. There are five shorter (2.16 Å) and one longer (2.18 Å) Mg–O bond lengths. In the sixth Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with six equivalent MgO6 octahedra, an edgeedge with one HfO6 octahedra, an edgeedge with one MnO6 octahedra, and edges with ten MgO6 octahedra. The corner-sharing octahedra tilt angles range from 0–6°. There are a spread of Mg–O bond distances ranging from 2.13–2.21 Å. Hf is bonded to six O atoms to form HfO6 octahedra that share corners with two equivalent HfO6 octahedra, corners with four equivalent MgO6 octahedra, and edges with twelve MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are two shorter (2.16 Å) and four longer (2.20 Å) Hf–O bond lengths. Mn is bonded to six O atoms to form MnO6 octahedra that share corners with two equivalent MnO6 octahedra, corners with four equivalent MgO6 octahedra, and edges with twelve MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are two shorter (2.16 Å) and four longer (2.24 Å) Mn–O bond lengths. There are seven inequivalent O sites. In the first O site, O is bonded to five Mg and one Mn atom to form a mixture of edge and corner-sharing OMg5Mn octahedra. The corner-sharing octahedra tilt angles range from 0–3°. In the second O site, O is bonded to five Mg and one Hf atom to form a mixture of edge and corner-sharing OHfMg5 octahedra. The corner-sharing octahedra tilt angles range from 0–3°. In the third O site, O is bonded to six Mg atoms to form OMg6 octahedra that share corners with six equivalent OMg6 octahedra and edges with twelve OMg5Mn octahedra. The corner-sharing octahedra tilt angles range from 1–3°. In the fourth O site, O is bonded to four Mg and two equivalent Mn atoms to form OMg4Mn2 octahedra that share corners with six OMg4Mn2 octahedra and edges with twelve OMg5Mn octahedra. The corner-sharing octahedral tilt angles are 0°. In the fifth O site, O is bonded to six Mg atoms to form OMg6 octahedra that share corners with six OMg4Mn2 octahedra and edges with twelve OMg5Mn octahedra. The corner-sharing octahedral tilt angles are 0°. In the sixth O site, O is bonded to four equivalent Mg and two equivalent Hf atoms to form OHf2Mg4 octahedra that share corners with six OMg6 octahedra and edges with twelve OHfMg5 octahedra. The corner-sharing octahedral tilt angles are 0°. In the seventh O site, O is bonded to five Mg and one Mn atom to form a mixture of edge and corner-sharing OMg5Mn octahedra. The corner-sharing octahedra tilt angles range from 0–3°. Both O–Mg bond lengths are 2.13 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on HfMg30NbO32 by Materials Project

Mg30HfNbO32 is alpha Po-derived structured and crystallizes in the tetragonal P4/mmm space group. The structure is three-dimensional. there are eight inequivalent Mg sites. In the first Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with two equivalent NbO6 octahedra, corners with four MgO6 octahedra, and edges with twelve MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are a spread of Mg–O bond distances ranging from 2.02–2.18 Å. In the second Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with two equivalent HfO6 octahedra, corners with four MgO6 octahedra, and edges with twelve MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are a spread of Mg–O bond distances ranging from 2.13–2.16 Å. In the third Mg site, Mg is bonded to six O atoms to form a mixture of edge and corner-sharing MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are four shorter (2.15 Å) and two longer (2.16 Å) Mg–O bond lengths. In the fourth Mg site, Mg is bonded to six O atoms to form a mixture of edge and corner-sharing MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are two shorter (2.15 Å) and four longer (2.16 Å) Mg–O bond lengths. In the fifth Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with six MgO6 octahedra, an edgeedge with one HfO6 octahedra, an edgeedge with one NbO6 octahedra, and edges with ten MgO6 octahedra. The corner-sharing octahedra tilt angles range from 2–7°. There are a spread of Mg–O bond distances ranging from 2.11–2.21 Å. In the sixth Mg site, Mg is bonded to six O atoms to form a mixture of edge and corner-sharing MgO6 octahedra. The corner-sharing octahedra tilt angles range from 0–3°. There are a spread of Mg–O bond distances ranging from 2.14–2.17 Å. In the seventh Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with six MgO6 octahedra, an edgeedge with one NbO6 octahedra, and edges with eleven MgO6 octahedra. The corner-sharing octahedra tilt angles range from 0–6°. There are two shorter (2.14 Å) and four longer (2.17 Å) Mg–O bond lengths. In the eighth Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with six MgO6 octahedra, an edgeedge with one HfO6 octahedra, and edges with eleven MgO6 octahedra. The corner-sharing octahedral tilt angles are 3°. There are a spread of Mg–O bond distances ranging from 2.11–2.21 Å. Hf is bonded to six O atoms to form HfO6 octahedra that share corners with two equivalent NbO6 octahedra, corners with four equivalent MgO6 octahedra, and edges with twelve MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are two shorter (2.07 Å) and four longer (2.16 Å) Hf–O bond lengths. Nb is bonded to six O atoms to form NbO6 octahedra that share corners with two equivalent HfO6 octahedra, corners with four equivalent MgO6 octahedra, and edges with twelve MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are two shorter (2.24 Å) and four longer (2.29 Å) Nb–O bond lengths. There are ten inequivalent O sites. In the first O site, O is bonded to five Mg and one Nb atom to form a mixture of edge and corner-sharing OMg5Nb octahedra. The corner-sharing octahedra tilt angles range from 0–3°. In the second O site, O is bonded to five Mg and one Hf atom to form OHfMg5 octahedra that share corners with six OMg5Nb octahedra and edges with twelve OHfMg5 octahedra. The corner-sharing octahedra tilt angles range from 0–3°. In the third O site, O is bonded to six Mg atoms to form a mixture of edge and corner-sharing OMg6 octahedra. The corner-sharing octahedra tilt angles range from 0–3°. Both O–Mg bond lengths are 2.14 Å. In the fourth O site, O is bonded to six Mg atoms to form a mixture of edge and corner-sharing OMg6 octahedra. The corner-sharing octahedra tilt angles range from 0–3°. In the fifth O site, O is bonded to six Mg atoms to form a mixture of edge and corner-sharing OMg6 octahedra. The corner-sharing octahedra tilt angles range from 0–3°. In the sixth O site, O is bonded to six Mg atoms to form OMg6 octahedra that share corners with six equivalent OMg6 octahedra and edges with twelve OMg5Nb octahedra. The corner-sharing octahedra tilt angles range from 1–4°. In the seventh O site, O is bonded to four equivalent Mg, one Hf, and one Nb atom to form OHfMg4Nb octahedra that share corners with six OHfMg4Nb octahedra and edges with twelve OMg6 octahedra. The corner-sharing octahedra tilt angles range from 0–5°. In the eighth O site, O is bonded to six Mg atoms to form OMg6 octahedra that share corners with six OHfMg4Nb octahedra and edges with twelve OMg5Nb octahedra. The corner-sharing octahedra tilt angles range from 0–5°. In the ninth O site, O is bonded to six Mg atoms to form a mixture of edge and corner-sharing OMg6 octahedra. The corner-sharing octahedra tilt angles range from 0–1°. In the tenth O site, O is bonded to five Mg and one Nb atom to form a mixture of edge and corner-sharing OMg5Nb octahedra. The corner-sharing octahedra tilt angles range from 0–3°. There are two shorter (2.11 Å) and two longer (2.17 Å) O–Mg bond lengths.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on CsHfMg14O15 by Materials Project

CsMg14HfO15 crystallizes in the orthorhombic Pmm2 space group. The structure is three-dimensional. Cs is bonded in a 5-coordinate geometry to five O atoms. There are a spread of Cs–O bond distances ranging from 2.81–3.02 Å. There are ten inequivalent Mg sites. In the first Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with two equivalent MgO6 octahedra, corners with two equivalent MgO5 square pyramids, edges with eight MgO6 octahedra, and edges with two equivalent MgO5 square pyramids. The corner-sharing octahedral tilt angles are 5°. There are a spread of Mg–O bond distances ranging from 2.01–2.23 Å. In the second Mg site, Mg is bonded to five O atoms to form MgO5 square pyramids that share corners with two equivalent MgO6 octahedra, corners with two equivalent MgO5 square pyramids, and edges with eight MgO6 octahedra. The corner-sharing octahedral tilt angles are 8°. There are one shorter (2.06 Å) and four longer (2.07 Å) Mg–O bond lengths. In the third Mg site, Mg is bonded to five O atoms to form MgO5 square pyramids that share a cornercorner with one MgO6 octahedra, corners with four equivalent MgO5 square pyramids, and edges with four MgO6 octahedra. The corner-sharing octahedral tilt angles are 3°. There are a spread of Mg–O bond distances ranging from 1.95–2.26 Å. In the fourth Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with four equivalent MgO6 octahedra, a cornercorner with one MgO5 square pyramid, edges with six MgO6 octahedra, and edges with three MgO5 square pyramids. The corner-sharing octahedra tilt angles range from 2–8°. There are a spread of Mg–O bond distances ranging from 2.04–2.28 Å. In the fifth Mg site, Mg is bonded to five O atoms to form MgO5 square pyramids that share a cornercorner with one MgO6 octahedra, corners with two equivalent MgO5 square pyramids, and edges with four MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are a spread of Mg–O bond distances ranging from 2.04–2.14 Å. In the sixth Mg site, Mg is bonded in a bent 150 degrees geometry to two equivalent O atoms. Both Mg–O bond lengths are 2.16 Å. In the seventh Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with four MgO6 octahedra, a cornercorner with one MgO5 square pyramid, edges with eight MgO6 octahedra, and edges with two equivalent MgO5 square pyramids. The corner-sharing octahedra tilt angles range from 1–14°. There are a spread of Mg–O bond distances ranging from 2.08–2.35 Å. In the eighth Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with four MgO6 octahedra, edges with six MgO6 octahedra, and edges with four MgO5 square pyramids. The corner-sharing octahedra tilt angles range from 1–3°. There are a spread of Mg–O bond distances ranging from 2.07–2.34 Å. In the ninth Mg site, Mg is bonded in a rectangular see-saw-like geometry to four O atoms. There are a spread of Mg–O bond distances ranging from 2.06–2.09 Å. In the tenth Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with four equivalent MgO6 octahedra, edges with seven MgO6 octahedra, and edges with three MgO5 square pyramids. The corner-sharing octahedra tilt angles range from 2–12°. There are a spread of Mg–O bond distances ranging from 2.07–2.34 Å. Hf is bonded in a 4-coordinate geometry to four O atoms. There are two shorter (1.99 Å) and two longer (2.14 Å) Hf–O bond lengths. There are eleven inequivalent O sites. In the first O site, O is bonded to one Cs and five Mg atoms to form distorted OCsMg5 octahedra that share corners with two equivalent OCsMg5 octahedra, a cornercorner with one OMg5 square pyramid, corners with two equivalent OCs2Mg3 trigonal bipyramids, edges with four OMg6 octahedra, and edges with four equivalent OMg5 square pyramids. The corner-sharing octahedral tilt angles are 6°. In the second O site, O is bonded to five Mg atoms to form OMg5 square pyramids that share a cornercorner with one OCsMg5 octahedra, corners with four OMg5 square pyramids, corners with two equivalent OCs2Mg3 trigonal bipyramids, and edges with eight OMg6 octahedra. The corner-sharing octahedral tilt angles are 0°. In the third O site, O is bonded to five Mg atoms to form OMg5 square pyramids that share corners with four OMg5 square pyramids, corners with two equivalent OHf2Mg3 trigonal bipyramids, edges with six OMg6 octahedra, and edges with two equivalent OMg5 square pyramids. In the fourth O site, O is bonded to five Mg atoms to form OMg5 square pyramids that share a cornercorner with one OMg6 octahedra, corners with five OMg5 square pyramids, and edges with five OCsMg5 octahedra. The corner-sharing octahedral tilt angles are 2°. In the fifth O site, O is bonded to six Mg atoms to form OMg6 octahedra that share corners with four equivalent OMg6 octahedra, a cornercorner with one OMg5 square pyramid, edges with three OMg6 octahedra, edges with five OMg5 square pyramids, and edges with two OCs2Mg3 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 1–2°. In the sixth O site, O is bonded to two equivalent Cs and three Mg atoms to form distorted OCs2Mg3 trigonal bipyramids that share corners with three OCsMg5 octahedra, corners with two equivalent OMg5 square pyramids, corners with four OCs2Mg3 trigonal bipyramids, and edges with two equivalent OMg6 octahedra. The corner-sharing octahedra tilt angles range from 0–47°. In the seventh O site, O is bonded to three Mg and two equivalent Hf atoms to form OHf2Mg3 trigonal bipyramids that share corners with three OMg5 square pyramids, corners with four OHf2Mg3 trigonal bipyramids, and edges with two equivalent OMg6 octahedra. In the eighth O site, O is bonded to six Mg atoms to form OMg6 octahedra that share corners with two equivalent OMg6 octahedra, corners with two equivalent OMg5 square pyramids, a cornercorner with one OCs2Mg3 trigonal bipyramid, edges with eight OCsMg5 octahedra, and edges with four OMg5 square pyramids. The corner-sharing octahedral tilt angles are 5°. In the ninth O site, O is bonded to five Mg atoms to form OMg5 square pyramids that share corners with two equivalent OMg6 octahedra, corners with four OMg5 square pyramids, a cornercorner with one OHf2Mg3 trigonal bipyramid, edges with six OMg6 octahedra, and edges with two equivalent OMg5 square pyramids. The corner-sharing octahedral tilt angles are 3°. In the tenth O site, O is bonded in a 5-coordinate geometry to one Cs, three Mg, and one Hf atom. In the eleventh O site, O is bonded to six Mg atoms to form OMg6 octahedra that share corners with four equivalent OMg6 octahedra, edges with five OCsMg5 octahedra, and edges with six OMg5 square pyramids. The corner-sharing octahedra tilt angles range from 3–12°.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on KHfMg6O7 by Materials Project

KMg6HfO7 crystallizes in the tetragonal P4mm space group. The structure is two-dimensional and consists of one KMg6HfO7 sheet oriented in the (0, 0, 1) direction. K is bonded in a 8-coordinate geometry to eight O atoms. There are four shorter (2.87 Å) and four longer (2.95 Å) K–O bond lengths. There are four inequivalent Mg sites. In the first Mg site, Mg is bonded to five O atoms to form a mixture of edge and corner-sharing MgO5 square pyramids. There are one shorter (1.98 Å) and four longer (2.10 Å) Mg–O bond lengths. In the second Mg site, Mg is bonded to five O atoms to form a mixture of distorted edge and corner-sharing MgO5 square pyramids. There are one shorter (2.08 Å) and four longer (2.11 Å) Mg–O bond lengths. In the third Mg site, Mg is bonded in a single-bond geometry to one O atom. The Mg–O bond length is 2.08 Å. In the fourth Mg site, Mg is bonded to five O atoms to form a mixture of distorted edge and corner-sharing MgO5 trigonal bipyramids. There are a spread of Mg–O bond distances ranging from 2.02–2.13 Å. Hf is bonded in a 5-coordinate geometry to five O atoms. There are one shorter (1.91 Å) and four longer (2.11 Å) Hf–O bond lengths. There are five inequivalent O sites. In the first O site, O is bonded to five Mg atoms to form distorted corner-sharing OMg5 trigonal bipyramids. In the second O site, O is bonded in a distorted single-bond geometry to four equivalent K and one Hf atom. In the third O site, O is bonded in a 5-coordinate geometry to five Mg atoms. In the fourth O site, O is bonded in a 3-coordinate geometry to two equivalent K, one Mg, and two equivalent Hf atoms. In the fifth O site, O is bonded to five Mg atoms to form a mixture of distorted edge and corner-sharing OMg5 square pyramids.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on HfMg30FeO32 by Materials Project

Mg30HfFeO32 is alpha Po-derived structured and crystallizes in the tetragonal P4/mmm space group. The structure is three-dimensional. there are eight inequivalent Mg sites. In the first Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with two equivalent FeO6 octahedra, corners with four MgO6 octahedra, and edges with twelve MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are a spread of Mg–O bond distances ranging from 2.04–2.19 Å. In the second Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with two equivalent HfO6 octahedra, corners with four MgO6 octahedra, and edges with twelve MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are a spread of Mg–O bond distances ranging from 2.13–2.18 Å. In the third Mg site, Mg is bonded to six O atoms to form a mixture of edge and corner-sharing MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are four shorter (2.14 Å) and two longer (2.17 Å) Mg–O bond lengths. In the fourth Mg site, Mg is bonded to six O atoms to form a mixture of edge and corner-sharing MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are two shorter (2.14 Å) and four longer (2.16 Å) Mg–O bond lengths. In the fifth Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with six MgO6 octahedra, an edgeedge with one HfO6 octahedra, an edgeedge with one FeO6 octahedra, and edges with ten MgO6 octahedra. The corner-sharing octahedra tilt angles range from 3–11°. There are a spread of Mg–O bond distances ranging from 2.07–2.24 Å. In the sixth Mg site, Mg is bonded to six O atoms to form a mixture of edge and corner-sharing MgO6 octahedra. The corner-sharing octahedra tilt angles range from 0–3°. There are a spread of Mg–O bond distances ranging from 2.14–2.17 Å. In the seventh Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with six MgO6 octahedra, an edgeedge with one FeO6 octahedra, and edges with eleven MgO6 octahedra. The corner-sharing octahedra tilt angles range from 1–6°. There are a spread of Mg–O bond distances ranging from 2.15–2.17 Å. In the eighth Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with six MgO6 octahedra, an edgeedge with one HfO6 octahedra, and edges with eleven MgO6 octahedra. The corner-sharing octahedra tilt angles range from 3–4°. There are a spread of Mg–O bond distances ranging from 2.10–2.20 Å. Hf is bonded to six O atoms to form HfO6 octahedra that share corners with two equivalent FeO6 octahedra, corners with four equivalent MgO6 octahedra, and edges with twelve MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are two shorter (2.04 Å) and four longer (2.12 Å) Hf–O bond lengths. Fe is bonded to six O atoms to form FeO6 octahedra that share corners with two equivalent HfO6 octahedra, corners with four equivalent MgO6 octahedra, and edges with twelve MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are four shorter (2.26 Å) and two longer (2.28 Å) Fe–O bond lengths. There are twelve inequivalent O sites. In the first O site, O is bonded to five Mg and one Fe atom to form OMg5Fe octahedra that share corners with six OHfMg5 octahedra and edges with twelve OMg5Fe octahedra. The corner-sharing octahedra tilt angles range from 0–3°. In the second O site, O is bonded to five Mg and one Hf atom to form OHfMg5 octahedra that share corners with six OMg5Fe octahedra and edges with twelve OHfMg5 octahedra. The corner-sharing octahedra tilt angles range from 0–4°. In the third O site, O is bonded to six Mg atoms to form a mixture of edge and corner-sharing OMg6 octahedra. The corner-sharing octahedra tilt angles range from 0–3°. In the fourth O site, O is bonded to six Mg atoms to form a mixture of edge and corner-sharing OMg6 octahedra. The corner-sharing octahedra tilt angles range from 0–4°. Both O–Mg bond lengths are 2.17 Å. In the fifth O site, O is bonded to five Mg and one Fe atom to form a mixture of edge and corner-sharing OMg5Fe octahedra. The corner-sharing octahedra tilt angles range from 0–3°. There are a spread of O–Mg bond distances ranging from 2.04–2.16 Å. In the sixth O site, O is bonded to six Mg atoms to form a mixture of edge and corner-sharing OMg6 octahedra. The corner-sharing octahedra tilt angles range from 0–4°. There are two shorter (2.10 Å) and two longer (2.17 Å) O–Mg bond lengths. In the seventh O site, O is bonded to six Mg atoms to form OMg6 octahedra that share corners with six equivalent OMg6 octahedra and edges with twelve OMg5Fe octahedra. The corner-sharing octahedra tilt angles range from 1–5°. In the eighth O site, O is bonded to four equivalent Mg, one Hf, and one Fe atom to form OHfMg4Fe octahedra that share corners with six OHfMg4Fe octahedra and edges with twelve OMg5Fe octahedra. The corner-sharing octahedra tilt angles range from 0–8°. In the ninth O site, O is bonded to six Mg atoms to form OMg6 octahedra that share corners with six OHfMg4Fe octahedra and edges with twelve OMg5Fe octahedra. The corner-sharing octahedra tilt angles range from 0–8°. In the tenth O site, O is bonded to six Mg atoms to form OMg6 octahedra that share corners with six OHfMg4Fe octahedra and edges with twelve OMg5Fe octahedra. The corner-sharing octahedra tilt angles range from 0–8°. There are two shorter (2.12 Å) and two longer (2.16 Å) O–Mg bond lengths. In the eleventh O site, O is bonded to six Mg atoms to form a mixture of edge and corner-sharing OMg6 octahedra. The corner-sharing octahedra tilt angles range from 0–2°. In the twelfth O site, O is bonded to six Mg atoms to form a mixture of edge and corner-sharing OMg6 octahedra. The corner-sharing octahedra tilt angles range from 0–4°. The O–Mg bond length is 2.15 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on HfMg30GaO32 by Materials Project

Mg30HfGaO32 is alpha Po-derived structured and crystallizes in the tetragonal P4/mmm space group. The structure is three-dimensional. there are eight inequivalent Mg sites. In the first Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with two equivalent GaO6 octahedra, corners with four MgO6 octahedra, and edges with twelve MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are a spread of Mg–O bond distances ranging from 1.97–2.20 Å. In the second Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with two equivalent HfO6 octahedra, corners with four MgO6 octahedra, and edges with twelve MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are a spread of Mg–O bond distances ranging from 2.13–2.16 Å. In the third Mg site, Mg is bonded to six O atoms to form a mixture of edge and corner-sharing MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are four shorter (2.13 Å) and two longer (2.17 Å) Mg–O bond lengths. In the fourth Mg site, Mg is bonded to six O atoms to form a mixture of edge and corner-sharing MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. All Mg–O bond lengths are 2.15 Å. In the fifth Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with six MgO6 octahedra, an edgeedge with one HfO6 octahedra, an edgeedge with one GaO6 octahedra, and edges with ten MgO6 octahedra. The corner-sharing octahedra tilt angles range from 2–11°. There are a spread of Mg–O bond distances ranging from 2.10–2.22 Å. In the sixth Mg site, Mg is bonded to six O atoms to form a mixture of edge and corner-sharing MgO6 octahedra. The corner-sharing octahedra tilt angles range from 0–3°. There are a spread of Mg–O bond distances ranging from 2.15–2.18 Å. In the seventh Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with six MgO6 octahedra, an edgeedge with one GaO6 octahedra, and edges with eleven MgO6 octahedra. The corner-sharing octahedra tilt angles range from 1–10°. There are two shorter (2.15 Å) and four longer (2.17 Å) Mg–O bond lengths. In the eighth Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with six MgO6 octahedra, an edgeedge with one HfO6 octahedra, and edges with eleven MgO6 octahedra. The corner-sharing octahedra tilt angles range from 1–3°. There are a spread of Mg–O bond distances ranging from 2.11–2.20 Å. Hf is bonded to six O atoms to form HfO6 octahedra that share corners with two equivalent GaO6 octahedra, corners with four equivalent MgO6 octahedra, and edges with twelve MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are two shorter (2.02 Å) and four longer (2.17 Å) Hf–O bond lengths. Ga is bonded to six O atoms to form GaO6 octahedra that share corners with two equivalent HfO6 octahedra, corners with four equivalent MgO6 octahedra, and edges with twelve MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are two shorter (2.31 Å) and four longer (2.34 Å) Ga–O bond lengths. There are nine inequivalent O sites. In the first O site, O is bonded to five Mg and one Ga atom to form OMg5Ga octahedra that share corners with six OHfMg5 octahedra and edges with twelve OMg5Ga octahedra. The corner-sharing octahedra tilt angles range from 0–5°. In the second O site, O is bonded to five Mg and one Hf atom to form OHfMg5 octahedra that share corners with six OMg5Ga octahedra and edges with twelve OHfMg5 octahedra. The corner-sharing octahedra tilt angles range from 0–2°. In the third O site, O is bonded to six Mg atoms to form a mixture of edge and corner-sharing OMg6 octahedra. The corner-sharing octahedra tilt angles range from 0–5°. In the fourth O site, O is bonded to six Mg atoms to form a mixture of edge and corner-sharing OMg6 octahedra. The corner-sharing octahedra tilt angles range from 0–2°. In the fifth O site, O is bonded to five Mg and one Ga atom to form a mixture of edge and corner-sharing OMg5Ga octahedra. The corner-sharing octahedra tilt angles range from 0–5°. There are a spread of O–Mg bond distances ranging from 1.97–2.17 Å. In the sixth O site, O is bonded to six Mg atoms to form OMg6 octahedra that share corners with six equivalent OMg6 octahedra and edges with twelve OMg5Ga octahedra. The corner-sharing octahedra tilt angles range from 1–5°. In the seventh O site, O is bonded to four equivalent Mg, one Hf, and one Ga atom to form OHfMg4Ga octahedra that share corners with six OHfMg4Ga octahedra and edges with twelve OMg5Ga octahedra. The corner-sharing octahedra tilt angles range from 0–8°. In the eighth O site, O is bonded to six Mg atoms to form OMg6 octahedra that share corners with six OHfMg4Ga octahedra and edges with twelve OMg5Ga octahedra. The corner-sharing octahedra tilt angles range from 0–8°. In the ninth O site, O is bonded to six Mg atoms to form a mixture of edge and corner-sharing OMg6 octahedra. The corner-sharing octahedra tilt angles range from 0–2°.

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