Engineering Papers⌕ Search

SEARCH · Engineering Papers

Results for “Mg”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 145 records · Page 8
All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

Materials Data on Mg(FeGe)6 by Materials Project

MgFe6Ge6 crystallizes in the hexagonal P6/mmm space group. The structure is three-dimensional. Mg is bonded to twelve equivalent Fe and eight Ge atoms to form distorted face-sharing MgFe12Ge8 hexagonal bipyramids. All Mg–Fe bond lengths are 3.21 Å. There are two shorter (2.72 Å) and six longer (2.91 Å) Mg–Ge bond lengths. Fe is bonded in a 12-coordinate geometry to two equivalent Mg, four equivalent Fe, and six Ge atoms. All Fe–Fe bond lengths are 2.52 Å. There are four shorter (2.47 Å) and two longer (2.62 Å) Fe–Ge bond lengths. There are three inequivalent Ge sites. In the first Ge site, Ge is bonded in a 12-coordinate geometry to three equivalent Mg and six equivalent Fe atoms. In the second Ge site, Ge is bonded in a 6-coordinate geometry to six equivalent Fe atoms. In the third Ge site, Ge is bonded in a 8-coordinate geometry to one Mg, six equivalent Fe, and one Ge atom. The Ge–Ge bond length is 2.55 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Mg(FeO2)2 by Materials Project

MgFe2O4 is Spinel-like structured and crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are six inequivalent Mg2+ sites. In the first Mg2+ site, Mg2+ is bonded to four O2- atoms to form MgO4 tetrahedra that share corners with three MgO6 octahedra and corners with nine FeO6 octahedra. The corner-sharing octahedra tilt angles range from 55–60°. There are a spread of Mg–O bond distances ranging from 1.99–2.03 Å. In the second Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with six FeO4 tetrahedra, edges with two MgO6 octahedra, and edges with four FeO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.08–2.12 Å. In the third Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share a cornercorner with one MgO4 tetrahedra, corners with five FeO4 tetrahedra, an edgeedge with one MgO6 octahedra, and edges with five FeO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.06–2.11 Å. In the fourth Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with two equivalent MgO4 tetrahedra, corners with four FeO4 tetrahedra, an edgeedge with one MgO6 octahedra, and edges with five FeO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.07–2.10 Å. In the fifth Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with six FeO4 tetrahedra, edges with two MgO6 octahedra, and edges with four FeO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.08–2.12 Å. In the sixth Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with six FeO4 tetrahedra, edges with two MgO6 octahedra, and edges with four FeO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.07–2.11 Å. There are twelve inequivalent Fe3+ sites. In the first Fe3+ site, Fe3+ is bonded to four O2- atoms to form FeO4 tetrahedra that share corners with six MgO6 octahedra and corners with six FeO6 octahedra. The corner-sharing octahedra tilt angles range from 55–59°. There are a spread of Fe–O bond distances ranging from 1.90–1.96 Å. In the second Fe3+ site, Fe3+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with two equivalent MgO4 tetrahedra, corners with four FeO4 tetrahedra, edges with three MgO6 octahedra, and edges with three FeO6 octahedra. There are a spread of Fe–O bond distances ranging from 2.00–2.07 Å. In the third Fe3+ site, Fe3+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with three equivalent MgO4 tetrahedra, corners with three equivalent FeO4 tetrahedra, edges with two MgO6 octahedra, and edges with four FeO6 octahedra. There are a spread of Fe–O bond distances ranging from 1.94–2.04 Å. In the fourth Fe3+ site, Fe3+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with two equivalent MgO4 tetrahedra, corners with four FeO4 tetrahedra, edges with three MgO6 octahedra, and edges with three FeO6 octahedra. There are a spread of Fe–O bond distances ranging from 2.00–2.08 Å. In the fifth Fe3+ site, Fe3+ is bonded to four O2- atoms to form FeO4 tetrahedra that share corners with six MgO6 octahedra and corners with six FeO6 octahedra. The corner-sharing octahedra tilt angles range from 55–59°. There are a spread of Fe–O bond distances ranging from 1.90–1.94 Å. In the sixth Fe3+ site, Fe3+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with six FeO4 tetrahedra, edges with two equivalent FeO6 octahedra, and edges with four MgO6 octahedra. There are a spread of Fe–O bond distances ranging from 2.03–2.09 Å. In the seventh Fe3+ site, Fe3+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with six FeO4 tetrahedra, edges with two equivalent FeO6 octahedra, and edges with four MgO6 octahedra. There are a spread of Fe–O bond distances ranging from 1.97–2.13 Å. In the eighth Fe3+ site, Fe3+ is bonded to six O2- atoms to form FeO6 octahedra that share a cornercorner with one MgO4 tetrahedra, corners with five FeO4 tetrahedra, edges with three MgO6 octahedra, and edges with three FeO6 octahedra. There are a spread of Fe–O bond distances ranging from 1.99–2.08 Å. In the ninth Fe3+ site, Fe3+ is bonded to four O2- atoms to form FeO4 tetrahedra that share corners with six MgO6 octahedra and corners with six FeO6 octahedra. The corner-sharing octahedra tilt angles range from 54–58°. There are a spread of Fe–O bond distances ranging from 1.91–1.94 Å. In the tenth Fe3+ site, Fe3+ is bonded to six O2- atoms to form FeO6 octahedra that share a cornercorner with one MgO4 tetrahedra, corners with five FeO4 tetrahedra, edges with three MgO6 octahedra, and edges with three FeO6 octahedra. There are a spread of Fe–O bond distances ranging from 1.98–2.09 Å. In the eleventh Fe3+ site, Fe3+ is bonded to four O2- atoms to form FeO4 tetrahedra that share corners with six MgO6 octahedra and corners with six FeO6 octahedra. The corner-sharing octahedra tilt angles range from 55–59°. There are a spread of Fe–O bond distances ranging from 1.90–1.97 Å. In the twelfth Fe3+ site, Fe3+ is bonded to four O2- atoms to form FeO4 tetrahedra that share corners with three MgO6 octahedra and corners with nine FeO6 octahedra. The corner-sharing octahedra tilt angles range from 55–60°. There are a spread of Fe–O bond distances ranging from 1.91–1.98 Å. There are twenty-four inequivalent O2- sites. In the first O2- site, O2- is bonded in a rectangular see-saw-like geometry to two Mg2+ and two Fe3+ atoms. In the second O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to one Mg2+ and three Fe3+ atoms. In the third O2- site, O2- is bonded in a rectangular see-saw-like geometry to two Mg2+ and two Fe3+ atoms. In the fourth O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Mg2+ and three Fe3+ atoms. In the fifth O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Mg2+ and three Fe3+ atoms. In the sixth O2- site, O2- is bonded in a distorted trigonal pyramidal geometry to two Mg2+ and two Fe3+ atoms. In the seventh O2- site, O2- is bonded in a rectangular see-saw-like geometry to two Mg2+ and two Fe3+ atoms. In the eighth O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Mg2+ and three Fe3+ atoms. In the ninth O2- site, O2- is bonded in a distorted trigonal pyramidal geometry to one Mg2+ and three Fe3+ atoms. In the tenth O2- site, O2- is bonded in a rectangular see-saw-like geometry to two Mg2+ and two Fe3+ atoms. In the eleventh O2- site, O2- is bonded in a rectangular see-saw-like geometry to two Mg2+ and two Fe3+ atoms. In the twelfth O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Mg2+ and three Fe3+ atoms. In the thirteenth O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Mg2+ and three Fe3+ atoms. In the fourteenth O2- site, O2- is bonded in a rectangular see-saw-like geometry to two Mg2+ and two Fe3+ atoms. In the fifteenth O2- site, O2- is bonded in a rectangular see-saw-like geometry to two Mg2+ and two Fe3+ atoms. In the sixteenth O2- site, O2- is bonded in a distorted trigonal pyramidal geometry to two Mg2+ and two Fe3+ atoms. In the seventeenth O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Mg2+ and three Fe3+ atoms. In the eighteenth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to two Mg2+ and two Fe3+ atoms. In the nineteenth O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Mg2+ and three Fe3+ atoms. In the twentieth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to two Mg2+ and two Fe3+ atoms. In the twenty-first O2- site, O2- is bonded in a rectangular see-saw-like geometry to four Fe3+ atoms. In the twenty-second O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Mg2+ and three Fe3+ atoms. In the twenty-third O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to one Mg2+ and three Fe3+ atoms. In the twenty-fourth O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Mg2+ and three Fe3+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Mg(FeO2)2 by Materials Project

MgFe2O4 is Spinel-like structured and crystallizes in the monoclinic Cm space group. The structure is three-dimensional. there are six inequivalent Mg2+ sites. In the first Mg2+ site, Mg2+ is bonded to four O2- atoms to form MgO4 tetrahedra that share corners with three MgO6 octahedra and corners with nine FeO6 octahedra. The corner-sharing octahedra tilt angles range from 56–59°. There are a spread of Mg–O bond distances ranging from 1.99–2.02 Å. In the second Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with six FeO4 tetrahedra, edges with two MgO6 octahedra, and edges with four FeO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.09–2.11 Å. In the third Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with two equivalent MgO4 tetrahedra, corners with four FeO4 tetrahedra, an edgeedge with one MgO6 octahedra, and edges with five FeO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.08–2.11 Å. In the fourth Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with six FeO4 tetrahedra, edges with two MgO6 octahedra, and edges with four FeO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.09–2.11 Å. In the fifth Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with six FeO4 tetrahedra, edges with two MgO6 octahedra, and edges with four equivalent FeO6 octahedra. There are five shorter (2.09 Å) and one longer (2.10 Å) Mg–O bond lengths. In the sixth Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share a cornercorner with one MgO4 tetrahedra, corners with five FeO4 tetrahedra, an edgeedge with one MgO6 octahedra, and edges with five FeO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.07–2.10 Å. There are nine inequivalent Fe3+ sites. In the first Fe3+ site, Fe3+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with two equivalent MgO4 tetrahedra, corners with four FeO4 tetrahedra, edges with three MgO6 octahedra, and edges with three FeO6 octahedra. There are a spread of Fe–O bond distances ranging from 2.01–2.09 Å. In the second Fe3+ site, Fe3+ is bonded to four O2- atoms to form FeO4 tetrahedra that share corners with six MgO6 octahedra and corners with six FeO6 octahedra. The corner-sharing octahedra tilt angles range from 56–57°. There are a spread of Fe–O bond distances ranging from 1.91–1.97 Å. In the third Fe3+ site, Fe3+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with three equivalent MgO4 tetrahedra, corners with three equivalent FeO4 tetrahedra, edges with two MgO6 octahedra, and edges with four FeO6 octahedra. There are a spread of Fe–O bond distances ranging from 1.99–2.10 Å. In the fourth Fe3+ site, Fe3+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with six FeO4 tetrahedra, edges with two equivalent FeO6 octahedra, and edges with four MgO6 octahedra. There are a spread of Fe–O bond distances ranging from 2.03–2.07 Å. In the fifth Fe3+ site, Fe3+ is bonded to four O2- atoms to form FeO4 tetrahedra that share corners with six MgO6 octahedra and corners with six FeO6 octahedra. The corner-sharing octahedra tilt angles range from 56–57°. There are a spread of Fe–O bond distances ranging from 1.91–1.96 Å. In the sixth Fe3+ site, Fe3+ is bonded to six O2- atoms to form FeO6 octahedra that share a cornercorner with one MgO4 tetrahedra, corners with five FeO4 tetrahedra, edges with three MgO6 octahedra, and edges with three FeO6 octahedra. There are a spread of Fe–O bond distances ranging from 2.00–2.10 Å. In the seventh Fe3+ site, Fe3+ is bonded to four O2- atoms to form FeO4 tetrahedra that share corners with six MgO6 octahedra and corners with six FeO6 octahedra. The corner-sharing octahedral tilt angles are 57°. There is two shorter (1.91 Å) and two longer (1.97 Å) Fe–O bond length. In the eighth Fe3+ site, Fe3+ is bonded to four O2- atoms to form FeO4 tetrahedra that share corners with six MgO6 octahedra and corners with six FeO6 octahedra. The corner-sharing octahedra tilt angles range from 57–58°. There is two shorter (1.91 Å) and two longer (1.97 Å) Fe–O bond length. In the ninth Fe3+ site, Fe3+ is bonded to four O2- atoms to form FeO4 tetrahedra that share corners with three MgO6 octahedra and corners with nine FeO6 octahedra. The corner-sharing octahedra tilt angles range from 56–58°. There is three shorter (1.93 Å) and one longer (1.98 Å) Fe–O bond length. There are eighteen inequivalent O2- sites. In the first O2- site, O2- is bonded in a rectangular see-saw-like geometry to two Mg2+ and two Fe3+ atoms. In the second O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to one Mg2+ and three Fe3+ atoms. In the third O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to one Mg2+ and three Fe3+ atoms. In the fourth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to two Mg2+ and two Fe3+ atoms. In the fifth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to one Mg2+ and three Fe3+ atoms. In the sixth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to one Mg2+ and three Fe3+ atoms. In the seventh O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to two Mg2+ and two Fe3+ atoms. In the eighth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to one Mg2+ and three Fe3+ atoms. In the ninth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to one Mg2+ and three Fe3+ atoms. In the tenth O2- site, O2- is bonded in a rectangular see-saw-like geometry to two Mg2+ and two Fe3+ atoms. In the eleventh O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to one Mg2+ and three Fe3+ atoms. In the twelfth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to two Mg2+ and two Fe3+ atoms. In the thirteenth O2- site, O2- is bonded to two Mg2+ and two equivalent Fe3+ atoms to form distorted corner-sharing OMg2Fe2 trigonal pyramids. In the fourteenth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to one Mg2+ and three Fe3+ atoms. In the fifteenth O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Mg2+ and three Fe3+ atoms. In the sixteenth O2- site, O2- is bonded to four Fe3+ atoms to form distorted OFe4 trigonal pyramids that share corners with four OMg2Fe2 trigonal pyramids and edges with three OMgFe3 trigonal pyramids. In the seventeenth O2- site, O2- is bonded to one Mg2+ and three Fe3+ atoms to form distorted OMgFe3 trigonal pyramids that share corners with four OMg2Fe2 trigonal pyramids and edges with three OFe4 trigonal pyramids. In the eighteenth O2- site, O2- is bonded to one Mg2+ and three Fe3+ atoms to form distorted OMgFe3 trigonal pyramids that share corners with three equivalent OMg2Fe2 trigonal pyramids and edges with three OFe4 trigonal pyramids.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Mg(GaO2)2 by Materials Project

MgGa2O4 is Spinel-like structured and crystallizes in the monoclinic Cm space group. The structure is three-dimensional. there are six inequivalent Mg2+ sites. In the first Mg2+ site, Mg2+ is bonded to four O2- atoms to form MgO4 tetrahedra that share corners with three MgO6 octahedra and corners with nine GaO6 octahedra. The corner-sharing octahedra tilt angles range from 57–60°. There is two shorter (1.97 Å) and two longer (2.00 Å) Mg–O bond length. In the second Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with two equivalent MgO4 tetrahedra, corners with four GaO4 tetrahedra, an edgeedge with one MgO6 octahedra, and edges with five GaO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.05–2.09 Å. In the third Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with six GaO4 tetrahedra, edges with two MgO6 octahedra, and edges with four equivalent GaO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.06–2.08 Å. In the fourth Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with six GaO4 tetrahedra, edges with two MgO6 octahedra, and edges with four GaO6 octahedra. There are four shorter (2.07 Å) and two longer (2.09 Å) Mg–O bond lengths. In the fifth Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share a cornercorner with one MgO4 tetrahedra, corners with five GaO4 tetrahedra, an edgeedge with one MgO6 octahedra, and edges with five GaO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.05–2.09 Å. In the sixth Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with six GaO4 tetrahedra, edges with two MgO6 octahedra, and edges with four GaO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.06–2.10 Å. There are nine inequivalent Ga3+ sites. In the first Ga3+ site, Ga3+ is bonded to four O2- atoms to form GaO4 tetrahedra that share corners with six MgO6 octahedra and corners with six GaO6 octahedra. The corner-sharing octahedra tilt angles range from 55–57°. There are a spread of Ga–O bond distances ranging from 1.88–1.93 Å. In the second Ga3+ site, Ga3+ is bonded to six O2- atoms to form GaO6 octahedra that share corners with two equivalent MgO4 tetrahedra, corners with four GaO4 tetrahedra, edges with three MgO6 octahedra, and edges with three GaO6 octahedra. There are a spread of Ga–O bond distances ranging from 1.96–2.07 Å. In the third Ga3+ site, Ga3+ is bonded to six O2- atoms to form GaO6 octahedra that share corners with three equivalent MgO4 tetrahedra, corners with three equivalent GaO4 tetrahedra, edges with two MgO6 octahedra, and edges with four GaO6 octahedra. There are a spread of Ga–O bond distances ranging from 1.96–2.08 Å. In the fourth Ga3+ site, Ga3+ is bonded to six O2- atoms to form GaO6 octahedra that share corners with six GaO4 tetrahedra, edges with two equivalent GaO6 octahedra, and edges with four MgO6 octahedra. There are a spread of Ga–O bond distances ranging from 1.99–2.05 Å. In the fifth Ga3+ site, Ga3+ is bonded to four O2- atoms to form GaO4 tetrahedra that share corners with six MgO6 octahedra and corners with six GaO6 octahedra. The corner-sharing octahedra tilt angles range from 55–57°. There is two shorter (1.87 Å) and two longer (1.91 Å) Ga–O bond length. In the sixth Ga3+ site, Ga3+ is bonded to six O2- atoms to form GaO6 octahedra that share a cornercorner with one MgO4 tetrahedra, corners with five GaO4 tetrahedra, edges with three MgO6 octahedra, and edges with three GaO6 octahedra. There are a spread of Ga–O bond distances ranging from 1.96–2.09 Å. In the seventh Ga3+ site, Ga3+ is bonded to four O2- atoms to form GaO4 tetrahedra that share corners with six MgO6 octahedra and corners with six GaO6 octahedra. The corner-sharing octahedra tilt angles range from 56–57°. There is two shorter (1.88 Å) and two longer (1.93 Å) Ga–O bond length. In the eighth Ga3+ site, Ga3+ is bonded to four O2- atoms to form GaO4 tetrahedra that share corners with six MgO6 octahedra and corners with six GaO6 octahedra. The corner-sharing octahedra tilt angles range from 56–58°. There are a spread of Ga–O bond distances ranging from 1.88–1.95 Å. In the ninth Ga3+ site, Ga3+ is bonded to four O2- atoms to form GaO4 tetrahedra that share corners with three MgO6 octahedra and corners with nine GaO6 octahedra. The corner-sharing octahedra tilt angles range from 56–59°. There are a spread of Ga–O bond distances ranging from 1.89–1.96 Å. There are eighteen inequivalent O2- sites. In the first O2- site, O2- is bonded in a rectangular see-saw-like geometry to two Mg2+ and two Ga3+ atoms. In the second O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Mg2+ and three Ga3+ atoms. In the third O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to one Mg2+ and three Ga3+ atoms. In the fourth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to two Mg2+ and two Ga3+ atoms. In the fifth O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Mg2+ and three Ga3+ atoms. In the sixth O2- site, O2- is bonded in a rectangular see-saw-like geometry to two Mg2+ and two Ga3+ atoms. In the seventh O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to one Mg2+ and three Ga3+ atoms. In the eighth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to one Mg2+ and three Ga3+ atoms. In the ninth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to one Mg2+ and three Ga3+ atoms. In the tenth O2- site, O2- is bonded in a rectangular see-saw-like geometry to two Mg2+ and two Ga3+ atoms. In the eleventh O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to one Mg2+ and three Ga3+ atoms. In the twelfth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to two Mg2+ and two Ga3+ atoms. In the thirteenth O2- site, O2- is bonded in a rectangular see-saw-like geometry to two Mg2+ and two equivalent Ga3+ atoms. In the fourteenth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to one Mg2+ and three Ga3+ atoms. In the fifteenth O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Mg2+ and three Ga3+ atoms. In the sixteenth O2- site, O2- is bonded to four Ga3+ atoms to form a mixture of distorted corner and edge-sharing OGa4 trigonal pyramids. In the seventeenth O2- site, O2- is bonded to one Mg2+ and three Ga3+ atoms to form a mixture of distorted corner and edge-sharing OMgGa3 trigonal pyramids. In the eighteenth O2- site, O2- is bonded to one Mg2+ and three Ga3+ atoms to form distorted edge-sharing OMgGa3 trigonal pyramids.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Mg(GaS2)2 by Materials Project

MgGa2S4 crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are six inequivalent Mg2+ sites. In the first Mg2+ site, Mg2+ is bonded to six S2- atoms to form MgS6 octahedra that share corners with ten GaS4 tetrahedra and edges with three MgS6 octahedra. There are a spread of Mg–S bond distances ranging from 2.59–2.71 Å. In the second Mg2+ site, Mg2+ is bonded to six S2- atoms to form MgS6 octahedra that share corners with six GaS4 tetrahedra and edges with six MgS6 octahedra. There are a spread of Mg–S bond distances ranging from 2.54–2.61 Å. In the third Mg2+ site, Mg2+ is bonded to six S2- atoms to form MgS6 octahedra that share corners with six GaS4 tetrahedra and edges with six MgS6 octahedra. There are a spread of Mg–S bond distances ranging from 2.54–2.61 Å. In the fourth Mg2+ site, Mg2+ is bonded to six S2- atoms to form MgS6 octahedra that share corners with ten GaS4 tetrahedra and edges with three MgS6 octahedra. There are a spread of Mg–S bond distances ranging from 2.59–2.70 Å. In the fifth Mg2+ site, Mg2+ is bonded to six S2- atoms to form MgS6 octahedra that share corners with eight GaS4 tetrahedra and edges with five MgS6 octahedra. There are a spread of Mg–S bond distances ranging from 2.55–2.73 Å. In the sixth Mg2+ site, Mg2+ is bonded to six S2- atoms to form MgS6 octahedra that share corners with eight GaS4 tetrahedra and edges with five MgS6 octahedra. There are a spread of Mg–S bond distances ranging from 2.54–2.73 Å. There are twelve inequivalent Ga3+ sites. In the first Ga3+ site, Ga3+ is bonded to four S2- atoms to form GaS4 tetrahedra that share corners with three MgS6 octahedra and corners with six GaS4 tetrahedra. The corner-sharing octahedra tilt angles range from 56–63°. There are a spread of Ga–S bond distances ranging from 2.20–2.36 Å. In the second Ga3+ site, Ga3+ is bonded to four S2- atoms to form GaS4 tetrahedra that share corners with four MgS6 octahedra and corners with five GaS4 tetrahedra. The corner-sharing octahedra tilt angles range from 50–64°. There are a spread of Ga–S bond distances ranging from 2.25–2.38 Å. In the third Ga3+ site, Ga3+ is bonded to four S2- atoms to form GaS4 tetrahedra that share corners with three MgS6 octahedra and corners with six GaS4 tetrahedra. The corner-sharing octahedra tilt angles range from 56–63°. There are a spread of Ga–S bond distances ranging from 2.20–2.36 Å. In the fourth Ga3+ site, Ga3+ is bonded to four S2- atoms to form GaS4 tetrahedra that share corners with four MgS6 octahedra and corners with five GaS4 tetrahedra. The corner-sharing octahedra tilt angles range from 50–64°. There are a spread of Ga–S bond distances ranging from 2.24–2.38 Å. In the fifth Ga3+ site, Ga3+ is bonded to four S2- atoms to form GaS4 tetrahedra that share corners with four MgS6 octahedra and corners with five GaS4 tetrahedra. The corner-sharing octahedra tilt angles range from 49–64°. There are a spread of Ga–S bond distances ranging from 2.24–2.38 Å. In the sixth Ga3+ site, Ga3+ is bonded to four S2- atoms to form GaS4 tetrahedra that share corners with five MgS6 octahedra, corners with three GaS4 tetrahedra, and an edgeedge with one GaS4 tetrahedra. The corner-sharing octahedra tilt angles range from 54–63°. There are a spread of Ga–S bond distances ranging from 2.24–2.35 Å. In the seventh Ga3+ site, Ga3+ is bonded to four S2- atoms to form GaS4 tetrahedra that share corners with three MgS6 octahedra and corners with six GaS4 tetrahedra. The corner-sharing octahedra tilt angles range from 56–63°. There are a spread of Ga–S bond distances ranging from 2.21–2.36 Å. In the eighth Ga3+ site, Ga3+ is bonded to four S2- atoms to form GaS4 tetrahedra that share corners with five MgS6 octahedra, corners with three GaS4 tetrahedra, and an edgeedge with one GaS4 tetrahedra. The corner-sharing octahedra tilt angles range from 53–62°. There are a spread of Ga–S bond distances ranging from 2.24–2.35 Å. In the ninth Ga3+ site, Ga3+ is bonded to four S2- atoms to form GaS4 tetrahedra that share corners with three MgS6 octahedra and corners with six GaS4 tetrahedra. The corner-sharing octahedra tilt angles range from 56–63°. There are a spread of Ga–S bond distances ranging from 2.21–2.36 Å. In the tenth Ga3+ site, Ga3+ is bonded to four S2- atoms to form GaS4 tetrahedra that share corners with four MgS6 octahedra and corners with five GaS4 tetrahedra. The corner-sharing octahedra tilt angles range from 50–64°. There are a spread of Ga–S bond distances ranging from 2.25–2.38 Å. In the eleventh Ga3+ site, Ga3+ is bonded to four S2- atoms to form GaS4 tetrahedra that share corners with five MgS6 octahedra, corners with three GaS4 tetrahedra, and an edgeedge with one GaS4 tetrahedra. The corner-sharing octahedra tilt angles range from 54–62°. There are a spread of Ga–S bond distances ranging from 2.24–2.35 Å. In the twelfth Ga3+ site, Ga3+ is bonded to four S2- atoms to form GaS4 tetrahedra that share corners with five MgS6 octahedra, corners with three GaS4 tetrahedra, and an edgeedge with one GaS4 tetrahedra. The corner-sharing octahedra tilt angles range from 54–63°. There are a spread of Ga–S bond distances ranging from 2.24–2.35 Å. There are twenty-four inequivalent S2- sites. In the first S2- site, S2- is bonded to three Mg2+ and one Ga3+ atom to form a mixture of distorted edge and corner-sharing SMg3Ga trigonal pyramids. In the second S2- site, S2- is bonded in a 4-coordinate geometry to two Mg2+ and two Ga3+ atoms. In the third S2- site, S2- is bonded in a trigonal non-coplanar geometry to three Ga3+ atoms. In the fourth S2- site, S2- is bonded in a trigonal planar geometry to one Mg2+ and two Ga3+ atoms. In the fifth S2- site, S2- is bonded in a trigonal non-coplanar geometry to three Ga3+ atoms. In the sixth S2- site, S2- is bonded in a trigonal non-coplanar geometry to three Ga3+ atoms. In the seventh S2- site, S2- is bonded in a distorted rectangular see-saw-like geometry to two Mg2+ and two Ga3+ atoms. In the eighth S2- site, S2- is bonded in a trigonal non-coplanar geometry to three Ga3+ atoms. In the ninth S2- site, S2- is bonded in a distorted rectangular see-saw-like geometry to two Mg2+ and two Ga3+ atoms. In the tenth S2- site, S2- is bonded to three Mg2+ and one Ga3+ atom to form a mixture of distorted edge and corner-sharing SMg3Ga trigonal pyramids. In the eleventh S2- site, S2- is bonded in a trigonal planar geometry to one Mg2+ and two Ga3+ atoms. In the twelfth S2- site, S2- is bonded in a trigonal planar geometry to one Mg2+ and two Ga3+ atoms. In the thirteenth S2- site, S2- is bonded in a trigonal non-coplanar geometry to three Ga3+ atoms. In the fourteenth S2- site, S2- is bonded to three Mg2+ and one Ga3+ atom to form a mixture of distorted edge and corner-sharing SMg3Ga trigonal pyramids. In the fifteenth S2- site, S2- is bonded to three Mg2+ and one Ga3+ atom to form a mixture of distorted edge and corner-sharing SMg3Ga trigonal pyramids. In the sixteenth S2- site, S2- is bonded to three Mg2+ and one Ga3+ atom to form a mixture of distorted edge and corner-sharing SMg3Ga trigonal pyramids. In the seventeenth S2- site, S2- is bonded to three Mg2+ and one Ga3+ atom to form a mixture of distorted edge and corner-sharing SMg3Ga trigonal pyramids. In the eighteenth S2- site, S2- is bonded in a distorted rectangular see-saw-like geometry to two Mg2+ and two Ga3+ atoms. In the nineteenth S2- site, S2- is bonded to three Mg2+ and one Ga3+ atom to form a mixture of distorted edge and corner-sharing SMg3Ga trigonal pyramids. In the twentieth S2- site, S2- is bonded to three Mg2+ and one Ga3+ atom to form a mixture of distorted edge and corner-sharing SMg3Ga trigonal pyramids. In the twenty-first S2- site, S2- is bonded in a trigonal planar geometry to one Mg2+ and two Ga3+ atoms. In the twenty-second S2- site, S2- is bonded in a trigonal non-coplanar geometry to three Ga3+ atoms. In the twenty-third S2- site, S2- is bonded in a trigonal non-coplanar geometry to three Ga3+ atoms. In the twenty-fourth S2- site, S2- is bonded in a trigonal non-coplanar geometry to three Ga3+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Mg(FeO2)4 by Materials Project

Mg(FeO2)4 crystallizes in the monoclinic Cm space group. The structure is three-dimensional. Mg is bonded to five O atoms to form MgO5 square pyramids that share corners with six FeO6 octahedra, edges with three FeO6 octahedra, edges with two equivalent MgO5 square pyramids, and a faceface with one FeO6 octahedra. The corner-sharing octahedra tilt angles range from 5–55°. There are a spread of Mg–O bond distances ranging from 2.05–2.15 Å. There are four inequivalent Fe sites. In the first Fe site, Fe is bonded to six O atoms to form distorted FeO6 octahedra that share corners with four FeO6 octahedra, edges with four FeO6 octahedra, and edges with two equivalent MgO5 square pyramids. The corner-sharing octahedra tilt angles range from 48–53°. There are a spread of Fe–O bond distances ranging from 1.92–2.24 Å. In the second Fe site, Fe is bonded to six O atoms to form distorted FeO6 octahedra that share corners with four FeO6 octahedra, corners with two equivalent MgO5 square pyramids, edges with four FeO6 octahedra, and a faceface with one MgO5 square pyramid. The corner-sharing octahedra tilt angles range from 48–54°. There are a spread of Fe–O bond distances ranging from 1.88–2.19 Å. In the third Fe site, Fe is bonded to six O atoms to form FeO6 octahedra that share corners with four FeO6 octahedra, corners with two equivalent MgO5 square pyramids, and edges with four FeO6 octahedra. The corner-sharing octahedra tilt angles range from 51–53°. There are a spread of Fe–O bond distances ranging from 1.95–2.13 Å. In the fourth Fe site, Fe is bonded to six O atoms to form FeO6 octahedra that share corners with four FeO6 octahedra, corners with two equivalent MgO5 square pyramids, edges with four FeO6 octahedra, and an edgeedge with one MgO5 square pyramid. The corner-sharing octahedra tilt angles range from 51–54°. There are a spread of Fe–O bond distances ranging from 1.93–2.16 Å. There are eight inequivalent O sites. In the first O site, O is bonded in a trigonal planar geometry to three Fe atoms. In the second O site, O is bonded in a trigonal planar geometry to three Fe atoms. In the third O site, O is bonded in a trigonal planar geometry to three Fe atoms. In the fourth O site, O is bonded to one Mg and three Fe atoms to form OMgFe3 trigonal pyramids that share corners with two equivalent OMgFe3 trigonal pyramids, edges with two equivalent OMg2Fe3 square pyramids, and edges with two equivalent OMg2Fe3 trigonal bipyramids. In the fifth O site, O is bonded in a trigonal non-coplanar geometry to three Fe atoms. In the sixth O site, O is bonded to two equivalent Mg and three Fe atoms to form distorted OMg2Fe3 trigonal bipyramids that share corners with two equivalent OMg2Fe3 square pyramids, an edgeedge with one OMg2Fe3 square pyramid, edges with two equivalent OMg2Fe3 trigonal bipyramids, and edges with two equivalent OMgFe3 trigonal pyramids. In the seventh O site, O is bonded to two equivalent Mg and three Fe atoms to form OMg2Fe3 square pyramids that share corners with two equivalent OMg2Fe3 trigonal bipyramids, edges with two equivalent OMg2Fe3 square pyramids, an edgeedge with one OMg2Fe3 trigonal bipyramid, and edges with two equivalent OMgFe3 trigonal pyramids. In the eighth O site, O is bonded in a trigonal non-coplanar geometry to three Fe atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Mg(BiO2)2 by Materials Project

Bi2MgO4 is Spinel-like structured and crystallizes in the monoclinic Cm space group. The structure is three-dimensional. there are six inequivalent Mg2+ sites. In the first Mg2+ site, Mg2+ is bonded to four O2- atoms to form MgO4 tetrahedra that share corners with three MgO6 octahedra and corners with nine BiO6 octahedra. The corner-sharing octahedra tilt angles range from 47–59°. There are a spread of Mg–O bond distances ranging from 2.04–2.12 Å. In the second Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with six BiO4 tetrahedra, edges with two MgO6 octahedra, and edges with four BiO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.14–2.21 Å. In the third Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with two equivalent MgO4 tetrahedra, corners with three BiO4 tetrahedra, a cornercorner with one BiO4 trigonal pyramid, an edgeedge with one MgO6 octahedra, and edges with five BiO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.08–2.54 Å. In the fourth Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with six BiO4 tetrahedra, edges with two MgO6 octahedra, and edges with four BiO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.14–2.20 Å. In the fifth Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with six BiO4 tetrahedra, edges with two MgO6 octahedra, and edges with four equivalent BiO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.15–2.30 Å. In the sixth Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share a cornercorner with one MgO4 tetrahedra, corners with three BiO4 tetrahedra, corners with two equivalent BiO4 trigonal pyramids, an edgeedge with one MgO6 octahedra, and edges with five BiO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.12–2.59 Å. There are nine inequivalent Bi3+ sites. In the first Bi3+ site, Bi3+ is bonded to six O2- atoms to form BiO6 octahedra that share corners with two equivalent MgO4 tetrahedra, corners with three BiO4 tetrahedra, a cornercorner with one BiO4 trigonal pyramid, edges with three MgO6 octahedra, and edges with three BiO6 octahedra. There are a spread of Bi–O bond distances ranging from 2.32–2.47 Å. In the second Bi3+ site, Bi3+ is bonded to four O2- atoms to form BiO4 tetrahedra that share corners with six MgO6 octahedra and corners with six BiO6 octahedra. The corner-sharing octahedra tilt angles range from 48–67°. There are a spread of Bi–O bond distances ranging from 2.21–2.35 Å. In the third Bi3+ site, Bi3+ is bonded to six O2- atoms to form BiO6 octahedra that share corners with three equivalent MgO4 tetrahedra, corners with three equivalent BiO4 trigonal pyramids, edges with two MgO6 octahedra, and edges with four BiO6 octahedra. There are a spread of Bi–O bond distances ranging from 2.36–2.57 Å. In the fourth Bi3+ site, Bi3+ is bonded to six O2- atoms to form BiO6 octahedra that share corners with six BiO4 tetrahedra, edges with two equivalent BiO6 octahedra, and edges with four MgO6 octahedra. There are a spread of Bi–O bond distances ranging from 2.35–2.42 Å. In the fifth Bi3+ site, Bi3+ is bonded to four O2- atoms to form BiO4 tetrahedra that share corners with six MgO6 octahedra and corners with six BiO6 octahedra. The corner-sharing octahedra tilt angles range from 50–69°. There are a spread of Bi–O bond distances ranging from 2.20–2.34 Å. In the sixth Bi3+ site, Bi3+ is bonded to six O2- atoms to form BiO6 octahedra that share a cornercorner with one MgO4 tetrahedra, corners with three BiO4 tetrahedra, corners with two equivalent BiO4 trigonal pyramids, edges with three MgO6 octahedra, and edges with three BiO6 octahedra. There are a spread of Bi–O bond distances ranging from 2.30–2.52 Å. In the seventh Bi3+ site, Bi3+ is bonded to four O2- atoms to form BiO4 tetrahedra that share corners with six MgO6 octahedra and corners with six BiO6 octahedra. The corner-sharing octahedra tilt angles range from 51–67°. There are a spread of Bi–O bond distances ranging from 2.21–2.32 Å. In the eighth Bi3+ site, Bi3+ is bonded to four O2- atoms to form BiO4 tetrahedra that share corners with six MgO6 octahedra and corners with six BiO6 octahedra. The corner-sharing octahedra tilt angles range from 47–69°. There are a spread of Bi–O bond distances ranging from 2.17–2.35 Å. In the ninth Bi3+ site, Bi3+ is bonded to four O2- atoms to form BiO4 trigonal pyramids that share corners with three MgO6 octahedra and corners with nine BiO6 octahedra. The corner-sharing octahedra tilt angles range from 37–73°. There are a spread of Bi–O bond distances ranging from 2.14–2.39 Å. There are eighteen inequivalent O2- sites. In the first O2- site, O2- is bonded in a rectangular see-saw-like geometry to two Mg2+ and two Bi3+ atoms. In the second O2- site, O2- is bonded in a distorted tetrahedral geometry to one Mg2+ and three Bi3+ atoms. In the third O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Mg2+ and three Bi3+ atoms. In the fourth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to two Mg2+ and two Bi3+ atoms. In the fifth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to one Mg2+ and three Bi3+ atoms. In the sixth O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Mg2+ and three Bi3+ atoms. In the seventh O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to two Mg2+ and two Bi3+ atoms. In the eighth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to one Mg2+ and three Bi3+ atoms. In the ninth O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Mg2+ and three Bi3+ atoms. In the tenth O2- site, O2- is bonded to two Mg2+ and two Bi3+ atoms to form a mixture of distorted edge and corner-sharing OMg2Bi2 tetrahedra. In the eleventh O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Mg2+ and three Bi3+ atoms. In the twelfth O2- site, O2- is bonded to two Mg2+ and two Bi3+ atoms to form a mixture of distorted edge and corner-sharing OMg2Bi2 trigonal pyramids. In the thirteenth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to two Mg2+ and two equivalent Bi3+ atoms. In the fourteenth O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Mg2+ and three Bi3+ atoms. In the fifteenth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to one Mg2+ and three Bi3+ atoms. In the sixteenth O2- site, O2- is bonded in a rectangular see-saw-like geometry to four Bi3+ atoms. In the seventeenth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to one Mg2+ and three Bi3+ atoms. In the eighteenth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to one Mg2+ and three Bi3+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Mg(CuO2)2 by Materials Project

MgCu2O4 is Spinel-like structured and crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are six inequivalent Mg2+ sites. In the first Mg2+ site, Mg2+ is bonded to four O2- atoms to form MgO4 tetrahedra that share corners with three MgO6 octahedra and corners with nine CuO6 octahedra. The corner-sharing octahedra tilt angles range from 57–60°. There are a spread of Mg–O bond distances ranging from 1.98–2.03 Å. In the second Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with six CuO4 tetrahedra, edges with two MgO6 octahedra, and edges with four CuO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.05–2.12 Å. In the third Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with two equivalent MgO4 tetrahedra, corners with four CuO4 tetrahedra, an edgeedge with one MgO6 octahedra, and edges with five CuO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.04–2.09 Å. In the fourth Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with six CuO4 tetrahedra, edges with two MgO6 octahedra, and edges with four CuO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.05–2.10 Å. In the fifth Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with six CuO4 tetrahedra, edges with two MgO6 octahedra, and edges with four CuO6 octahedra. There are four shorter (2.05 Å) and two longer (2.08 Å) Mg–O bond lengths. In the sixth Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share a cornercorner with one MgO4 tetrahedra, corners with five CuO4 tetrahedra, an edgeedge with one MgO6 octahedra, and edges with five CuO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.05–2.09 Å. There are twelve inequivalent Cu3+ sites. In the first Cu3+ site, Cu3+ is bonded to six O2- atoms to form CuO6 octahedra that share corners with two equivalent MgO4 tetrahedra, corners with four CuO4 tetrahedra, edges with three MgO6 octahedra, and edges with three CuO6 octahedra. There are a spread of Cu–O bond distances ranging from 1.91–2.04 Å. In the second Cu3+ site, Cu3+ is bonded to four O2- atoms to form CuO4 tetrahedra that share corners with six MgO6 octahedra and corners with six CuO6 octahedra. The corner-sharing octahedra tilt angles range from 56–59°. There is two shorter (1.92 Å) and two longer (1.93 Å) Cu–O bond length. In the third Cu3+ site, Cu3+ is bonded to six O2- atoms to form CuO6 octahedra that share corners with three equivalent MgO4 tetrahedra, corners with three equivalent CuO4 tetrahedra, edges with two MgO6 octahedra, and edges with four CuO6 octahedra. There are a spread of Cu–O bond distances ranging from 1.96–2.04 Å. In the fourth Cu3+ site, Cu3+ is bonded to six O2- atoms to form CuO6 octahedra that share corners with two equivalent MgO4 tetrahedra, corners with four CuO4 tetrahedra, edges with three MgO6 octahedra, and edges with three CuO6 octahedra. There are a spread of Cu–O bond distances ranging from 1.91–2.04 Å. In the fifth Cu3+ site, Cu3+ is bonded to six O2- atoms to form CuO6 octahedra that share corners with six CuO4 tetrahedra, edges with two equivalent CuO6 octahedra, and edges with four MgO6 octahedra. There are a spread of Cu–O bond distances ranging from 1.92–2.04 Å. In the sixth Cu3+ site, Cu3+ is bonded to four O2- atoms to form CuO4 tetrahedra that share corners with six MgO6 octahedra and corners with six CuO6 octahedra. The corner-sharing octahedra tilt angles range from 55–60°. There are a spread of Cu–O bond distances ranging from 1.90–1.92 Å. In the seventh Cu3+ site, Cu3+ is bonded to six O2- atoms to form CuO6 octahedra that share corners with six CuO4 tetrahedra, edges with two equivalent CuO6 octahedra, and edges with four MgO6 octahedra. There are a spread of Cu–O bond distances ranging from 1.92–2.04 Å. In the eighth Cu3+ site, Cu3+ is bonded to six O2- atoms to form CuO6 octahedra that share a cornercorner with one MgO4 tetrahedra, corners with five CuO4 tetrahedra, edges with three MgO6 octahedra, and edges with three CuO6 octahedra. There are a spread of Cu–O bond distances ranging from 1.93–2.09 Å. In the ninth Cu3+ site, Cu3+ is bonded to four O2- atoms to form CuO4 tetrahedra that share corners with six MgO6 octahedra and corners with six CuO6 octahedra. The corner-sharing octahedra tilt angles range from 54–61°. There is one shorter (1.91 Å) and three longer (1.93 Å) Cu–O bond length. In the tenth Cu3+ site, Cu3+ is bonded to six O2- atoms to form CuO6 octahedra that share a cornercorner with one MgO4 tetrahedra, corners with five CuO4 tetrahedra, edges with three MgO6 octahedra, and edges with three CuO6 octahedra. There are a spread of Cu–O bond distances ranging from 1.93–2.10 Å. In the eleventh Cu3+ site, Cu3+ is bonded to four O2- atoms to form CuO4 tetrahedra that share corners with six MgO6 octahedra and corners with six CuO6 octahedra. The corner-sharing octahedra tilt angles range from 56–60°. There are a spread of Cu–O bond distances ranging from 1.92–1.99 Å. In the twelfth Cu3+ site, Cu3+ is bonded to four O2- atoms to form CuO4 tetrahedra that share corners with three MgO6 octahedra and corners with nine CuO6 octahedra. The corner-sharing octahedra tilt angles range from 55–62°. There are a spread of Cu–O bond distances ranging from 1.90–1.98 Å. There are twenty-four inequivalent O2- sites. In the first O2- site, O2- is bonded to two Mg2+ and two Cu3+ atoms to form a mixture of distorted edge and corner-sharing OMg2Cu2 trigonal pyramids. In the second O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Mg2+ and three Cu3+ atoms. In the third O2- site, O2- is bonded to two Mg2+ and two Cu3+ atoms to form a mixture of distorted edge and corner-sharing OMg2Cu2 trigonal pyramids. In the fourth O2- site, O2- is bonded to one Mg2+ and three Cu3+ atoms to form a mixture of distorted edge and corner-sharing OMgCu3 trigonal pyramids. In the fifth O2- site, O2- is bonded to two Mg2+ and two Cu3+ atoms to form a mixture of distorted edge and corner-sharing OMg2Cu2 trigonal pyramids. In the sixth O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Mg2+ and three Cu3+ atoms. In the seventh O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Mg2+ and three Cu3+ atoms. In the eighth O2- site, O2- is bonded in a rectangular see-saw-like geometry to two Mg2+ and two Cu3+ atoms. In the ninth O2- site, O2- is bonded to two Mg2+ and two Cu3+ atoms to form a mixture of distorted edge and corner-sharing OMg2Cu2 trigonal pyramids. In the tenth O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Mg2+ and three Cu3+ atoms. In the eleventh O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to one Mg2+ and three Cu3+ atoms. In the twelfth O2- site, O2- is bonded in a rectangular see-saw-like geometry to two Mg2+ and two Cu3+ atoms. In the thirteenth O2- site, O2- is bonded in a rectangular see-saw-like geometry to two Mg2+ and two Cu3+ atoms. In the fourteenth O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Mg2+ and three Cu3+ atoms. In the fifteenth O2- site, O2- is bonded to two Mg2+ and two Cu3+ atoms to form a mixture of distorted edge and corner-sharing OMg2Cu2 trigonal pyramids. In the sixteenth O2- site, O2- is bonded in a rectangular see-saw-like geometry to two Mg2+ and two Cu3+ atoms. In the seventeenth O2- site, O2- is bonded to two Mg2+ and two Cu3+ atoms to form distorted corner-sharing OMg2Cu2 trigonal pyramids. In the eighteenth O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Mg2+ and three Cu3+ atoms. In the nineteenth O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Mg2+ and three Cu3+ atoms. In the twentieth O2- site, O2- is bonded to two Mg2+ and two Cu3+ atoms to form a mixture of distorted edge and corner-sharing OMg2Cu2 trigonal pyramids. In the twenty-first O2- site, O2- is bonded in a rectangular see-saw-like geometry to four Cu3+ atoms. In the twenty-second O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to one Mg2+ and three Cu3+ atoms. In the twenty-third O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Mg2+ and three Cu3+ atoms. In the twenty-fourth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to one Mg2+ and three Cu3+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Mg(CoO2)2 by Materials Project

MgCo2O4 is Spinel-like structured and crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are six inequivalent Mg2+ sites. In the first Mg2+ site, Mg2+ is bonded to four O2- atoms to form MgO4 tetrahedra that share corners with three MgO6 octahedra and corners with nine CoO6 octahedra. The corner-sharing octahedra tilt angles range from 57–61°. There are a spread of Mg–O bond distances ranging from 1.94–2.05 Å. In the second Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with six CoO4 tetrahedra, edges with two MgO6 octahedra, and edges with four CoO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.04–2.08 Å. In the third Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with two equivalent MgO4 tetrahedra, corners with four CoO4 tetrahedra, an edgeedge with one MgO6 octahedra, and edges with five CoO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.00–2.10 Å. In the fourth Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with six CoO4 tetrahedra, edges with two MgO6 octahedra, and edges with four CoO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.03–2.08 Å. In the fifth Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with six CoO4 tetrahedra, edges with two MgO6 octahedra, and edges with four CoO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.03–2.08 Å. In the sixth Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share a cornercorner with one MgO4 tetrahedra, corners with five CoO4 tetrahedra, an edgeedge with one MgO6 octahedra, and edges with five CoO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.02–2.06 Å. There are twelve inequivalent Co3+ sites. In the first Co3+ site, Co3+ is bonded to six O2- atoms to form CoO6 octahedra that share corners with two equivalent MgO4 tetrahedra, corners with four CoO4 tetrahedra, edges with three MgO6 octahedra, and edges with three CoO6 octahedra. There are a spread of Co–O bond distances ranging from 1.91–1.98 Å. In the second Co3+ site, Co3+ is bonded to four O2- atoms to form CoO4 tetrahedra that share corners with six MgO6 octahedra and corners with six CoO6 octahedra. The corner-sharing octahedra tilt angles range from 54–60°. There are a spread of Co–O bond distances ranging from 1.85–1.94 Å. In the third Co3+ site, Co3+ is bonded to six O2- atoms to form CoO6 octahedra that share corners with three equivalent MgO4 tetrahedra, corners with three equivalent CoO4 tetrahedra, edges with two MgO6 octahedra, and edges with four CoO6 octahedra. There are a spread of Co–O bond distances ranging from 1.89–1.98 Å. In the fourth Co3+ site, Co3+ is bonded to six O2- atoms to form CoO6 octahedra that share corners with two equivalent MgO4 tetrahedra, corners with four CoO4 tetrahedra, edges with three MgO6 octahedra, and edges with three CoO6 octahedra. There are a spread of Co–O bond distances ranging from 1.91–1.98 Å. In the fifth Co3+ site, Co3+ is bonded to six O2- atoms to form CoO6 octahedra that share corners with six CoO4 tetrahedra, edges with two equivalent CoO6 octahedra, and edges with four MgO6 octahedra. There are a spread of Co–O bond distances ranging from 1.92–1.97 Å. In the sixth Co3+ site, Co3+ is bonded to four O2- atoms to form CoO4 tetrahedra that share corners with six MgO6 octahedra and corners with six CoO6 octahedra. The corner-sharing octahedra tilt angles range from 54–60°. There are a spread of Co–O bond distances ranging from 1.85–1.93 Å. In the seventh Co3+ site, Co3+ is bonded to six O2- atoms to form CoO6 octahedra that share corners with six CoO4 tetrahedra, edges with two equivalent CoO6 octahedra, and edges with four MgO6 octahedra. There is two shorter (1.93 Å) and four longer (1.96 Å) Co–O bond length. In the eighth Co3+ site, Co3+ is bonded to six O2- atoms to form CoO6 octahedra that share a cornercorner with one MgO4 tetrahedra, corners with five CoO4 tetrahedra, edges with three MgO6 octahedra, and edges with three CoO6 octahedra. There are a spread of Co–O bond distances ranging from 1.92–1.98 Å. In the ninth Co3+ site, Co3+ is bonded to four O2- atoms to form CoO4 tetrahedra that share corners with six MgO6 octahedra and corners with six CoO6 octahedra. The corner-sharing octahedra tilt angles range from 55–60°. There is two shorter (1.85 Å) and two longer (1.94 Å) Co–O bond length. In the tenth Co3+ site, Co3+ is bonded to six O2- atoms to form CoO6 octahedra that share a cornercorner with one MgO4 tetrahedra, corners with five CoO4 tetrahedra, edges with three MgO6 octahedra, and edges with three CoO6 octahedra. There are a spread of Co–O bond distances ranging from 1.91–1.99 Å. In the eleventh Co3+ site, Co3+ is bonded to four O2- atoms to form CoO4 tetrahedra that share corners with six MgO6 octahedra and corners with six CoO6 octahedra. The corner-sharing octahedra tilt angles range from 55–60°. There is two shorter (1.86 Å) and two longer (1.94 Å) Co–O bond length. In the twelfth Co3+ site, Co3+ is bonded to four O2- atoms to form CoO4 tetrahedra that share corners with three MgO6 octahedra and corners with nine CoO6 octahedra. The corner-sharing octahedra tilt angles range from 56–62°. There are a spread of Co–O bond distances ranging from 1.89–1.97 Å. There are twenty-four inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to two Mg2+ and two Co3+ atoms. In the second O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Mg2+ and three Co3+ atoms. In the third O2- site, O2- is bonded in a rectangular see-saw-like geometry to two Mg2+ and two Co3+ atoms. In the fourth O2- site, O2- is bonded to one Mg2+ and three Co3+ atoms to form distorted corner-sharing OMgCo3 trigonal pyramids. In the fifth O2- site, O2- is bonded in a rectangular see-saw-like geometry to two Mg2+ and two Co3+ atoms. In the sixth O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Mg2+ and three Co3+ atoms. In the seventh O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Mg2+ and three Co3+ atoms. In the eighth O2- site, O2- is bonded in a rectangular see-saw-like geometry to two Mg2+ and two Co3+ atoms. In the ninth O2- site, O2- is bonded in a rectangular see-saw-like geometry to two Mg2+ and two Co3+ atoms. In the tenth O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Mg2+ and three Co3+ atoms. In the eleventh O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Mg2+ and three Co3+ atoms. In the twelfth O2- site, O2- is bonded in a rectangular see-saw-like geometry to two Mg2+ and two Co3+ atoms. In the thirteenth O2- site, O2- is bonded in a rectangular see-saw-like geometry to two Mg2+ and two Co3+ atoms. In the fourteenth O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Mg2+ and three Co3+ atoms. In the fifteenth O2- site, O2- is bonded in a rectangular see-saw-like geometry to two Mg2+ and two Co3+ atoms. In the sixteenth O2- site, O2- is bonded in a rectangular see-saw-like geometry to two Mg2+ and two Co3+ atoms. In the seventeenth O2- site, O2- is bonded to two Mg2+ and two Co3+ atoms to form distorted corner-sharing OMg2Co2 trigonal pyramids. In the eighteenth O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Mg2+ and three Co3+ atoms. In the nineteenth O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Mg2+ and three Co3+ atoms. In the twentieth O2- site, O2- is bonded in a rectangular see-saw-like geometry to two Mg2+ and two Co3+ atoms. In the twenty-first O2- site, O2- is bonded to four Co3+ atoms to form distorted corner-sharing OCo4 trigonal pyramids. In the twenty-second O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Mg2+ and three Co3+ atoms. In the twenty-third O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Mg2+ and three Co3+ atoms. In the twenty-fourth O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Mg2+ and three Co3+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Mg(SbO2)2 by Materials Project

MgSb2O4 crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are six inequivalent Mg2+ sites. In the first Mg2+ site, Mg2+ is bonded to four O2- atoms to form MgO4 tetrahedra that share a cornercorner with one MgO6 octahedra and corners with two equivalent MgO5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 60°. There are a spread of Mg–O bond distances ranging from 1.96–2.14 Å. In the second Mg2+ site, Mg2+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of Mg–O bond distances ranging from 2.02–2.40 Å. In the third Mg2+ site, Mg2+ is bonded to five O2- atoms to form distorted corner-sharing MgO5 trigonal bipyramids. There are a spread of Mg–O bond distances ranging from 1.98–2.49 Å. In the fourth Mg2+ site, Mg2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Mg–O bond distances ranging from 2.01–2.78 Å. In the fifth Mg2+ site, Mg2+ is bonded in a distorted rectangular see-saw-like geometry to four O2- atoms. There are a spread of Mg–O bond distances ranging from 1.98–2.01 Å. In the sixth Mg2+ site, Mg2+ is bonded to six O2- atoms to form distorted corner-sharing MgO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.01–2.58 Å. There are twelve inequivalent Sb3+ sites. In the first Sb3+ site, Sb3+ is bonded in a 3-coordinate geometry to three O2- atoms. There are a spread of Sb–O bond distances ranging from 1.95–2.07 Å. In the second Sb3+ site, Sb3+ is bonded in a distorted T-shaped geometry to three O2- atoms. There are a spread of Sb–O bond distances ranging from 1.96–2.07 Å. In the third Sb3+ site, Sb3+ is bonded in a distorted trigonal non-coplanar geometry to three O2- atoms. There are a spread of Sb–O bond distances ranging from 1.97–2.04 Å. In the fourth Sb3+ site, Sb3+ is bonded in a rectangular see-saw-like geometry to four O2- atoms. There are a spread of Sb–O bond distances ranging from 1.94–2.56 Å. In the fifth Sb3+ site, Sb3+ is bonded in a distorted T-shaped geometry to three O2- atoms. There are a spread of Sb–O bond distances ranging from 1.96–2.03 Å. In the sixth Sb3+ site, Sb3+ is bonded in a distorted T-shaped geometry to three O2- atoms. There are a spread of Sb–O bond distances ranging from 1.99–2.12 Å. In the seventh Sb3+ site, Sb3+ is bonded in a distorted T-shaped geometry to three O2- atoms. There are a spread of Sb–O bond distances ranging from 1.96–2.02 Å. In the eighth Sb3+ site, Sb3+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of Sb–O bond distances ranging from 2.05–2.73 Å. In the ninth Sb3+ site, Sb3+ is bonded in a distorted T-shaped geometry to three O2- atoms. There are a spread of Sb–O bond distances ranging from 1.99–2.02 Å. In the tenth Sb3+ site, Sb3+ is bonded in a 5-coordinate geometry to three O2- atoms. There are a spread of Sb–O bond distances ranging from 2.00–2.06 Å. In the eleventh Sb3+ site, Sb3+ is bonded in a distorted T-shaped geometry to three O2- atoms. There are a spread of Sb–O bond distances ranging from 1.96–2.02 Å. In the twelfth Sb3+ site, Sb3+ is bonded in a 3-coordinate geometry to three O2- atoms. There are a spread of Sb–O bond distances ranging from 1.95–2.11 Å. There are twenty-four inequivalent O2- sites. In the first O2- site, O2- is bonded in a 3-coordinate geometry to two Mg2+ and one Sb3+ atom. In the second O2- site, O2- is bonded in a 3-coordinate geometry to one Mg2+ and two Sb3+ atoms. In the third O2- site, O2- is bonded in a distorted trigonal planar geometry to two Mg2+ and one Sb3+ atom. In the fourth O2- site, O2- is bonded in a bent 120 degrees geometry to one Mg2+ and one Sb3+ atom. In the fifth O2- site, O2- is bonded in a distorted trigonal planar geometry to two Mg2+ and one Sb3+ atom. In the sixth O2- site, O2- is bonded in a distorted water-like geometry to one Mg2+ and one Sb3+ atom. In the seventh O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two Sb3+ atoms. In the eighth O2- site, O2- is bonded in a 3-coordinate geometry to one Mg2+ and two Sb3+ atoms. In the ninth O2- site, O2- is bonded in a distorted T-shaped geometry to two Mg2+ and one Sb3+ atom. In the tenth O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to one Mg2+ and two Sb3+ atoms. In the eleventh O2- site, O2- is bonded in a 3-coordinate geometry to one Mg2+ and two Sb3+ atoms. In the twelfth O2- site, O2- is bonded in a distorted trigonal planar geometry to one Mg2+ and two Sb3+ atoms. In the thirteenth O2- site, O2- is bonded in a 4-coordinate geometry to two Mg2+ and two Sb3+ atoms. In the fourteenth O2- site, O2- is bonded in a 3-coordinate geometry to one Mg2+ and two Sb3+ atoms. In the fifteenth O2- site, O2- is bonded in a distorted trigonal planar geometry to two Mg2+ and one Sb3+ atom. In the sixteenth O2- site, O2- is bonded in a 3-coordinate geometry to two Mg2+ and two Sb3+ atoms. In the seventeenth O2- site, O2- is bonded in a 4-coordinate geometry to two Mg2+ and two Sb3+ atoms. In the eighteenth O2- site, O2- is bonded in a bent 120 degrees geometry to two Sb3+ atoms. In the nineteenth O2- site, O2- is bonded in a trigonal non-coplanar geometry to one Mg2+ and two Sb3+ atoms. In the twentieth O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to two Mg2+ and one Sb3+ atom. In the twenty-first O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two Sb3+ atoms. In the twenty-second O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Mg2+ and one Sb3+ atom. In the twenty-third O2- site, O2- is bonded in a distorted trigonal planar geometry to one Mg2+ and two Sb3+ atoms. In the twenty-fourth O2- site, O2- is bonded in a distorted trigonal planar geometry to one Mg2+ and two Sb3+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Mg(PO5)2 by Materials Project

Mg(PO5)2 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. Mg is bonded to six O atoms to form distorted MgO6 octahedra that share corners with four equivalent PO4 tetrahedra. There are four shorter (2.01 Å) and two longer (2.63 Å) Mg–O bond lengths. P is bonded to four O atoms to form PO4 tetrahedra that share corners with two equivalent MgO6 octahedra. The corner-sharing octahedra tilt angles range from 14–28°. There are a spread of P–O bond distances ranging from 1.49–1.70 Å. There are five inequivalent O sites. In the first O site, O is bonded in a distorted single-bond geometry to one P and one O atom. The O–O bond length is 1.58 Å. In the second O site, O is bonded in a distorted bent 120 degrees geometry to one P and one O atom. The O–O bond length is 1.39 Å. In the third O site, O is bonded in a linear geometry to one Mg and one P atom. In the fourth O site, O is bonded in a trigonal non-coplanar geometry to one Mg and two O atoms. In the fifth O site, O is bonded in a bent 150 degrees geometry to one Mg and one P atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Mg(ClO3)2 by Materials Project

Mg(O3Cl)2 crystallizes in the monoclinic C2/m space group. The structure is one-dimensional and consists of two Mg(O3Cl)2 ribbons oriented in the (0, 0, 1) direction. Mg is bonded in an octahedral geometry to six O atoms. There are two shorter (2.02 Å) and four longer (2.16 Å) Mg–O bond lengths. There are two inequivalent O sites. In the first O site, O is bonded in a 2-coordinate geometry to one Mg and one O atom. The O–O bond length is 1.28 Å. In the second O site, O is bonded in a bent 120 degrees geometry to one Mg and one Cl atom. The O–Cl bond length is 1.62 Å. Cl is bonded in a single-bond geometry to one O atom.

36 MATERIALS SCIENCE↗
DOE OSTI2022

Synthesis and Mg 2+ deintercalation in manganese spinel nanocrystals

Transition metal oxides are promising materials as cathodes for divalent batteries with high capacity under high voltage. A major challenge is the sluggish kinetics of intercalation of divalent cations into the oxide host. Tailoring of the size, composition and crystal structure of oxides is a necessary strategy to alleviate these barriers, which challenges our control of their synthesis. In this work, we selectively synthesize spinel-type Mg x Mn 3-x O 4 nanocrystals with different Mg/Mn ratios and investigate their ability to electrochemically shuttle Mg 2+ ions. Crystal-chemical characterization of the reaction outcomes was conducted with X-ray diffraction, X-ray absorption spectroscopy, electron microscopy, and elemental analysis. Both 5 nm thick MgMn 2 O 4 nanosheets and 10 nm Mg 0.41 Mn 2.59 O 4 nanocubes underwent reversible Mg 2+ deintercalation, yet no obvious reaction was observed in 60 nm Mg 1.2 Mn 1.8 O 4 nanocubes. Our results suggest that both the size of the spinel nanocrystals and the Mg/Mn ratios play a role in the observed behaviour. The advances in the synthesis of spinel oxide nanocrystals achieved, and their correlation with Mg 2+ deintercalation, pave the way toward the precise synthesis of multivalent cathode materials that fundamentally overcome barriers to practical application.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2021

Coexisting normal and intruder configurations in 32 Mg

Situated in the so-called “island of inversion,” the nucleus 32 Mg is considered as an archetypal example of the disappearance of magicity at N = 20. We report on high statistics in-beam spectroscopy of 32 Mg with a unique approach, in that two direct reaction probes with different sensitivities to the underlying nuclear structure are employed at the same time. More specifically, states in 32 Mg were populated by knockout reactions starting from 33 Mg and 34 Si, lying inside and outside the island of inversion, respectively. The momentum distributions of the reaction residues and the cross sections leading to the individual final states were confronted with eikonal-based reaction calculations, yielding a significantly updated level scheme for 32 Mg and spin-parity assignments. By fully exploiting observables obtained in this measurement, a variety of structures coexisting in 32 Mg was unraveled. Comparisons with theoretical predictions based on shell-model overlaps allowed for clear discrimination between different structural models, revealing that the complete theoretical description of this key nucleus is yet to be achieved.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗
DOE OSTI2020

Intercalation of Mg into a Few-Layer Phyllomanganate in Non-aqueous Electrolytes at Room Temperature

The use of oxide cathodes in Mg batteries would unlock a potential energy storage system that delivers high-energy density. However, poor kinetics of Mg diffusion in known solid oxide lattices strongly limits reversible intercalation, which motivates the sustained exploration of new candidates. Herein, nanocrystals of a few-layer phyllomanganate, reminiscent of the mineral vernadite, were shown to have considerable electrochemical activity toward Mg intercalation at room temperature, where it delivered similar to 190 mAh g- 1 at similar to 1.9 V (vs Mg/Mg 2+ ) in batteries paired with a Mg metal anode. Multimodal characterization confirmed the notable degree of reversible intercalation by probing the structural, compositional, and redox changes undertaken by the oxide. Distinct levels of Mg activity were also observed while varying the content of small amounts of lattice water and the temperature of the reaction. The results reaffirm the prospects for operational Mg batteries using oxide cathode in moderate conditions, overcoming current limits of performance of this prospective technology.

25 ENERGY STORAGE↗
DOE OSTI2020

Nanoscale Mg–B via Surfactant Ball Milling of MgB 2 : Morphology, Composition, and Improved Hydrogen Storage Properties

Metal borides have attracted the attention of researchers due to their useful physical properties and unique ability to form high hydrogen-capacity metal borohydrides. We demonstrate improved hydrogen storage properties of a nanoscale Mg–B material made by surfactant ball milling MgB 2 in a mixture of heptane, oleic acid, and oleylamine. Transmission electron microscopy data show that Mg–B nanoplatelets are produced with sizes ranging from 5 to 50 nm, which agglomerate upon ethanol washing to produce an agglomerated nanoscale Mg–B material of micron-sized particles with some surfactant still remaining. X-ray diffraction measurements reveal a two-component material where 32% of the solid is a strained crystalline solid maintaining the hexagonal structure with the remainder being amorphous. Fourier transform infrared shows that the oleate binds in a “bridge-bonding” fashion preferentially to magnesium rather than boron, which is confirmed by density functional theory calculations. The Mg–B nanoscale material is deficient in boron relative to bulk MgB 2 with a Mg–B ratio of ~1:0.75. The nanoscale MgB 0.75 material has a disrupted B–B ring network as indicated by X-ray absorption measurements. Hydrogenation experiments at 700 bar and 280 °C show that it partially hydrogenates at temperatures 100 °C below the threshold for bulk MgB 2 hydrogenation. In addition, upon heating to 200 °C, the H–H bond-breaking ability increases ~10-fold according to hydrogen–deuterium exchange experiments due to desorption of oleate at the surface. This behavior would make the nanoscale Mg–B material useful as an additive where rapid H–H bond breaking is needed.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2022

First-Principles Elucidation of Initial Dehydrogenation Pathways in Mg(BH 4 ) 2

Complex borohydrides such as Mg(BH 4 ) 2 offer one of highest capacities to chemically store hydrogen for onboard applications; however, it suffers greatly from kinetic constraints that prevent realization of full capacity and reversibility. Understanding these kinetic limitations solely from experiments is extremely challenging due to the unusual complexity of various competing elemental reaction steps involved during the de/rehydrogenation reaction. This work aims to map out the energetics associated with initial dehydrogenation of Mg(BH 4 ) 2 from first-principles simulations and to identify the preferred reaction pathways. Our calculations suggest the rate-limiting step during BH 4 – –B 3 H 8 – conversion is the formation of the B 2 H 7 – intermediate. We further emphasize and clarify that the B 3 H 8 – and H – intermediates, formed during initial Mg(BH 4 ) 2 decomposition, appear as molecular species that are embedded in the Mg–BH 4 –Mg matrix as evidenced in the nuclear magnetic resonance measurements and not as bulk MgH 2 and Mg(B 3 H 8 ) 2 as previously assumed in theoretical predictions of the thermodynamics.

08 HYDROGEN↗
DOE OSTI2020

High Capacity for Mg 2+ Deintercalation in Spinel Vanadium Oxide Nanocrystals

Nonaqueous Mg batteries can theoretically reach high energy density with cost-effective materials, yet no such device to date has performance competitive with Li-ion technologies. A major barrier is the need for oxide cathodes that combine high capacity and voltage. Very few oxides have shown intrinsic ability for Mg 2+ intercalation in electrolytes with acceptably low content of H2O. Herein, we demonstrate that nanocrystals of MgV 2 O 4 can reach high capacity for Mg 2+ deintercalation with a mechanism that preserves their spinel framework, validated through measurements with different chemical and structural sensitivity. The structural stability contrasts with other phases where reaching high capacity required distortions that introduce undesirable mechanical strain. The favorable properties of the oxide allowed cycling in a full cell with Mg metal. This work reveals new insights into the viability of multivalent intercalation in oxides, meeting a milestone toward the feasibility of high-voltage batteries with either Mg metal or Mg-ion anodes.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗