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DOE OSTI2020

Materials Data on Li8CaSn7 by Materials Project

Li8CaSn7 crystallizes in the orthorhombic Cmcm space group. The structure is three-dimensional. there are five inequivalent Li sites. In the first Li site, Li is bonded in a 8-coordinate geometry to two equivalent Li, one Ca, and five Sn atoms. Both Li–Li bond lengths are 2.96 Å. The Li–Ca bond length is 3.16 Å. There are one shorter (2.77 Å) and four longer (2.96 Å) Li–Sn bond lengths. In the second Li site, Li is bonded in a 9-coordinate geometry to one Ca and six Sn atoms. The Li–Ca bond length is 3.22 Å. There are a spread of Li–Sn bond distances ranging from 2.88–3.32 Å. In the third Li site, Li is bonded in a 4-coordinate geometry to two equivalent Li and five Sn atoms. Both Li–Li bond lengths are 2.98 Å. There are a spread of Li–Sn bond distances ranging from 2.87–3.28 Å. In the fourth Li site, Li is bonded in a 3-coordinate geometry to one Li, one Ca, and five Sn atoms. The Li–Li bond length is 3.01 Å. The Li–Ca bond length is 3.21 Å. There are a spread of Li–Sn bond distances ranging from 2.81–3.08 Å. In the fifth Li site, Li is bonded to eight Li and four equivalent Sn atoms to form a mixture of corner and face-sharing LiLi8Sn4 cuboctahedra. All Li–Sn bond lengths are 3.23 Å. Ca is bonded in a 10-coordinate geometry to five Li and ten Sn atoms. There are a spread of Ca–Sn bond distances ranging from 3.38–3.46 Å. There are five inequivalent Sn sites. In the first Sn site, Sn is bonded in a 6-coordinate geometry to four Li and two equivalent Sn atoms. Both Sn–Sn bond lengths are 3.08 Å. In the second Sn site, Sn is bonded in a 7-coordinate geometry to seven Li and two equivalent Sn atoms. In the third Sn site, Sn is bonded in a 9-coordinate geometry to five Li, two equivalent Ca, and one Sn atom. The Sn–Sn bond length is 2.95 Å. In the fourth Sn site, Sn is bonded in a 4-coordinate geometry to four equivalent Li and two equivalent Ca atoms. In the fifth Sn site, Sn is bonded in a 12-coordinate geometry to eight Li, two equivalent Ca, and two Sn atoms. The Sn–Sn bond length is 2.96 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on KCa3 by Materials Project

KCa3 is beta Cu3Ti-like structured and crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. K is bonded to twelve Ca atoms to form KCa12 cuboctahedra that share corners with four equivalent KCa12 cuboctahedra, corners with eight equivalent CaK4Ca8 cuboctahedra, edges with eight equivalent KCa12 cuboctahedra, edges with sixteen equivalent CaK4Ca8 cuboctahedra, faces with four equivalent KCa12 cuboctahedra, and faces with fourteen CaK4Ca8 cuboctahedra. There are four shorter (4.03 Å) and eight longer (4.08 Å) K–Ca bond lengths. There are two inequivalent Ca sites. In the first Ca site, Ca is bonded to four equivalent K and eight Ca atoms to form CaK4Ca8 cuboctahedra that share corners with twelve equivalent CaK4Ca8 cuboctahedra, edges with eight equivalent KCa12 cuboctahedra, edges with sixteen CaK4Ca8 cuboctahedra, faces with four equivalent KCa12 cuboctahedra, and faces with fourteen CaK4Ca8 cuboctahedra. There are four shorter (4.03 Å) and four longer (4.08 Å) Ca–Ca bond lengths. In the second Ca site, Ca is bonded to four equivalent K and eight equivalent Ca atoms to form CaK4Ca8 cuboctahedra that share corners with four equivalent CaK4Ca8 cuboctahedra, corners with eight equivalent KCa12 cuboctahedra, edges with twenty-four CaK4Ca8 cuboctahedra, faces with six equivalent KCa12 cuboctahedra, and faces with twelve CaK4Ca8 cuboctahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ca5Sn3H by Materials Project

Ca5Sn3H crystallizes in the tetragonal I4/mcm space group. The structure is three-dimensional. there are two inequivalent Ca sites. In the first Ca site, Ca is bonded to six Sn atoms to form distorted corner-sharing CaSn6 octahedra. The corner-sharing octahedra tilt angles range from 0–52°. There are four shorter (3.23 Å) and two longer (3.74 Å) Ca–Sn bond lengths. In the second Ca site, Ca is bonded in a distorted single-bond geometry to five Sn and one H atom. There are a spread of Ca–Sn bond distances ranging from 3.30–3.40 Å. The Ca–H bond length is 2.38 Å. There are two inequivalent Sn sites. In the first Sn site, Sn is bonded in a 10-coordinate geometry to ten Ca atoms. In the second Sn site, Sn is bonded in a 9-coordinate geometry to eight Ca and one Sn atom. The Sn–Sn bond length is 2.95 Å. H is bonded in a tetrahedral geometry to four equivalent Ca atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on SrCa3 by Materials Project

SrCa3 is alpha bismuth trifluoride structured and crystallizes in the cubic Fm-3m space group. The structure is three-dimensional. Sr is bonded in a body-centered cubic geometry to eight equivalent Ca atoms. All Sr–Ca bond lengths are 3.85 Å. There are two inequivalent Ca sites. In the first Ca site, Ca is bonded in a body-centered cubic geometry to four equivalent Sr and four equivalent Ca atoms. All Ca–Ca bond lengths are 3.85 Å. In the second Ca site, Ca is bonded in a body-centered cubic geometry to eight equivalent Ca atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ca11Si9As16 by Materials Project

Ca11Si9As16 crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are eleven inequivalent Ca2+ sites. In the first Ca2+ site, Ca2+ is bonded to six As+2.62- atoms to form a mixture of corner and edge-sharing CaAs6 octahedra. The corner-sharing octahedra tilt angles range from 5–8°. There are a spread of Ca–As bond distances ranging from 2.98–3.06 Å. In the second Ca2+ site, Ca2+ is bonded to six As+2.62- atoms to form a mixture of corner and edge-sharing CaAs6 octahedra. The corner-sharing octahedra tilt angles range from 2–8°. There are a spread of Ca–As bond distances ranging from 2.97–3.10 Å. In the third Ca2+ site, Ca2+ is bonded to six As+2.62- atoms to form a mixture of corner and edge-sharing CaAs6 octahedra. The corner-sharing octahedra tilt angles range from 2–8°. There are a spread of Ca–As bond distances ranging from 2.98–3.09 Å. In the fourth Ca2+ site, Ca2+ is bonded to six As+2.62- atoms to form a mixture of corner and edge-sharing CaAs6 octahedra. The corner-sharing octahedra tilt angles range from 1–5°. There are a spread of Ca–As bond distances ranging from 2.96–3.16 Å. In the fifth Ca2+ site, Ca2+ is bonded to six As+2.62- atoms to form a mixture of corner and edge-sharing CaAs6 octahedra. The corner-sharing octahedra tilt angles range from 4–8°. There are a spread of Ca–As bond distances ranging from 2.98–3.12 Å. In the sixth Ca2+ site, Ca2+ is bonded to six As+2.62- atoms to form a mixture of corner and edge-sharing CaAs6 octahedra. The corner-sharing octahedra tilt angles range from 2–6°. There are a spread of Ca–As bond distances ranging from 2.97–3.16 Å. In the seventh Ca2+ site, Ca2+ is bonded to six As+2.62- atoms to form a mixture of corner and edge-sharing CaAs6 octahedra. The corner-sharing octahedra tilt angles range from 2–6°. There are a spread of Ca–As bond distances ranging from 2.97–3.17 Å. In the eighth Ca2+ site, Ca2+ is bonded to six As+2.62- atoms to form a mixture of corner and edge-sharing CaAs6 octahedra. The corner-sharing octahedra tilt angles range from 1–6°. There are a spread of Ca–As bond distances ranging from 2.99–3.17 Å. In the ninth Ca2+ site, Ca2+ is bonded to six As+2.62- atoms to form a mixture of corner and edge-sharing CaAs6 octahedra. The corner-sharing octahedra tilt angles range from 3–8°. There are a spread of Ca–As bond distances ranging from 2.94–3.12 Å. In the tenth Ca2+ site, Ca2+ is bonded to six As+2.62- atoms to form a mixture of corner and edge-sharing CaAs6 octahedra. The corner-sharing octahedra tilt angles range from 4–8°. There are a spread of Ca–As bond distances ranging from 2.96–3.11 Å. In the eleventh Ca2+ site, Ca2+ is bonded to six As+2.62- atoms to form a mixture of corner and edge-sharing CaAs6 octahedra. The corner-sharing octahedra tilt angles range from 3–6°. There are a spread of Ca–As bond distances ranging from 2.96–3.13 Å. There are nine inequivalent Si+2.22+ sites. In the first Si+2.22+ site, Si+2.22+ is bonded in a trigonal non-coplanar geometry to three As+2.62- atoms. There are a spread of Si–As bond distances ranging from 2.35–2.42 Å. In the second Si+2.22+ site, Si+2.22+ is bonded in a trigonal non-coplanar geometry to three As+2.62- atoms. There are a spread of Si–As bond distances ranging from 2.39–2.47 Å. In the third Si+2.22+ site, Si+2.22+ is bonded in a trigonal non-coplanar geometry to three As+2.62- atoms. There are a spread of Si–As bond distances ranging from 2.36–2.43 Å. In the fourth Si+2.22+ site, Si+2.22+ is bonded in a trigonal non-coplanar geometry to three As+2.62- atoms. There are a spread of Si–As bond distances ranging from 2.35–2.42 Å. In the fifth Si+2.22+ site, Si+2.22+ is bonded in a trigonal non-coplanar geometry to three As+2.62- atoms. There are one shorter (2.39 Å) and two longer (2.40 Å) Si–As bond lengths. In the sixth Si+2.22+ site, Si+2.22+ is bonded in a trigonal non-coplanar geometry to three As+2.62- atoms. There are a spread of Si–As bond distances ranging from 2.39–2.41 Å. In the seventh Si+2.22+ site, Si+2.22+ is bonded in a trigonal non-coplanar geometry to three As+2.62- atoms. There are a spread of Si–As bond distances ranging from 2.39–2.41 Å. In the eighth Si+2.22+ site, Si+2.22+ is bonded in a trigonal non-coplanar geometry to three As+2.62- atoms. There are a spread of Si–As bond distances ranging from 2.39–2.44 Å. In the ninth Si+2.22+ site, Si+2.22+ is bonded in a 2-coordinate geometry to five As+2.62- atoms. There are a spread of Si–As bond distances ranging from 2.70–3.04 Å. There are sixteen inequivalent As+2.62- sites. In the first As+2.62- site, As+2.62- is bonded in a 6-coordinate geometry to three Ca2+ and three Si+2.22+ atoms. In the second As+2.62- site, As+2.62- is bonded to four Ca2+ and two Si+2.22+ atoms to form AsCa4Si2 octahedra that share corners with eight AsCa4Si2 octahedra and edges with eight AsCa5Si octahedra. The corner-sharing octahedra tilt angles range from 5–93°. In the third As+2.62- site, As+2.62- is bonded to four Ca2+ and two Si+2.22+ atoms to form a mixture of corner and edge-sharing AsCa4Si2 octahedra. The corner-sharing octahedra tilt angles range from 5–93°. In the fourth As+2.62- site, As+2.62- is bonded to three Ca2+ and three Si+2.22+ atoms to form distorted AsCa3Si3 octahedra that share corners with four AsCa5Si octahedra, edges with five AsCa4Si2 octahedra, and edges with two equivalent AsCa3Si2 square pyramids. The corner-sharing octahedra tilt angles range from 3–83°. In the fifth As+2.62- site, As+2.62- is bonded to four Ca2+ and two Si+2.22+ atoms to form AsCa4Si2 octahedra that share corners with four AsCa4Si2 octahedra, corners with two equivalent AsCa3Si2 square pyramids, and edges with nine AsCa4Si2 octahedra. The corner-sharing octahedra tilt angles range from 3–7°. In the sixth As+2.62- site, As+2.62- is bonded to five Ca2+ and one Si+2.22+ atom to form a mixture of corner and edge-sharing AsCa5Si octahedra. The corner-sharing octahedra tilt angles range from 4–88°. In the seventh As+2.62- site, As+2.62- is bonded to five Ca2+ and one Si+2.22+ atom to form AsCa5Si octahedra that share corners with five AsCa5Si octahedra, corners with two equivalent AsCa3Si2 square pyramids, and edges with ten AsCa4Si2 octahedra. The corner-sharing octahedra tilt angles range from 3–87°. In the eighth As+2.62- site, As+2.62- is bonded to five Ca2+ and one Si+2.22+ atom to form AsCa5Si octahedra that share corners with five AsCa5Si octahedra, a cornercorner with one AsCa3Si2 square pyramid, and edges with seven AsCa5Si octahedra. The corner-sharing octahedra tilt angles range from 3–83°. In the ninth As+2.62- site, As+2.62- is bonded to three Ca2+ and two Si+2.22+ atoms to form distorted AsCa3Si2 square pyramids that share corners with eight AsCa4Si2 octahedra and edges with three AsCa5Si octahedra. The corner-sharing octahedra tilt angles range from 4–96°. In the tenth As+2.62- site, As+2.62- is bonded to four Ca2+ and two Si+2.22+ atoms to form a mixture of corner and edge-sharing AsCa4Si2 octahedra. The corner-sharing octahedra tilt angles range from 5–92°. In the eleventh As+2.62- site, As+2.62- is bonded to four Ca2+ and two Si+2.22+ atoms to form AsCa4Si2 octahedra that share corners with eight AsCa5Si octahedra and edges with eight AsCa4Si2 octahedra. The corner-sharing octahedra tilt angles range from 3–92°. In the twelfth As+2.62- site, As+2.62- is bonded in a 5-coordinate geometry to three Ca2+ and three Si+2.22+ atoms. In the thirteenth As+2.62- site, As+2.62- is bonded to four Ca2+ and two Si+2.22+ atoms to form AsCa4Si2 octahedra that share corners with four AsCa4Si2 octahedra, corners with two equivalent AsCa3Si2 square pyramids, and edges with nine AsCa5Si octahedra. The corner-sharing octahedra tilt angles range from 5–7°. In the fourteenth As+2.62- site, As+2.62- is bonded to five Ca2+ and one Si+2.22+ atom to form AsCa5Si octahedra that share corners with five AsCa4Si2 octahedra and edges with nine AsCa5Si octahedra. The corner-sharing octahedra tilt angles range from 4–92°. In the fifteenth As+2.62- site, As+2.62- is bonded to five Ca2+ and one Si+2.22+ atom to form AsCa5Si octahedra that share corners with seven AsCa4Si2 octahedra, edges with nine AsCa4Si2 octahedra, and an edgeedge with one AsCa3Si2 square pyramid. The corner-sharing octahedra tilt angles range from 3–92°. In the sixteenth As+2.62- site, As+2.62- is bonded to five Ca2+ and one Si+2.22+ atom to form AsCa5Si octahedra that share corners with five AsCa4Si2 octahedra, a cornercorner with one AsCa3Si2 square pyramid, and edges with seven AsCa5Si octahedra. The corner-sharing octahedra tilt angles range from 3–6°.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ca4Cd3Au by Materials Project

Ca4AuCd3 is Heusler-like structured and crystallizes in the tetragonal P4/mmm space group. The structure is three-dimensional. there are two inequivalent Ca sites. In the first Ca site, Ca is bonded in a distorted body-centered cubic geometry to four equivalent Au and four equivalent Cd atoms. All Ca–Au bond lengths are 3.24 Å. All Ca–Cd bond lengths are 3.34 Å. In the second Ca site, Ca is bonded in a body-centered cubic geometry to eight Cd atoms. There are four shorter (3.29 Å) and four longer (3.30 Å) Ca–Cd bond lengths. Au is bonded in a body-centered cubic geometry to eight equivalent Ca atoms. There are two inequivalent Cd sites. In the first Cd site, Cd is bonded in a body-centered cubic geometry to eight Ca atoms. In the second Cd site, Cd is bonded in a body-centered cubic geometry to eight equivalent Ca atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on CaCeMg14 by Materials Project

CaMg14Ce crystallizes in the orthorhombic Amm2 space group. The structure is three-dimensional. Ca is bonded to ten Mg and two equivalent Ce atoms to form CaCe2Mg10 cuboctahedra that share corners with six equivalent CaCe2Mg10 cuboctahedra, corners with twelve MgMg12 cuboctahedra, edges with two equivalent CeCa2Mg10 cuboctahedra, edges with sixteen MgCa2Ce2Mg8 cuboctahedra, faces with two equivalent CeCa2Mg10 cuboctahedra, and faces with eighteen MgMg12 cuboctahedra. There are a spread of Ca–Mg bond distances ranging from 3.22–3.31 Å. Both Ca–Ce bond lengths are 3.34 Å. There are thirteen inequivalent Mg sites. In the first Mg site, Mg is bonded to twelve Mg atoms to form MgMg12 cuboctahedra that share corners with four equivalent CeCa2Mg10 cuboctahedra, corners with fourteen MgCa2Ce2Mg8 cuboctahedra, edges with eighteen MgMg12 cuboctahedra, faces with two equivalent CaCe2Mg10 cuboctahedra, and faces with eighteen MgMg12 cuboctahedra. There are a spread of Mg–Mg bond distances ranging from 3.23–3.34 Å. In the second Mg site, Mg is bonded to twelve Mg atoms to form MgMg12 cuboctahedra that share corners with four equivalent CaCe2Mg10 cuboctahedra, corners with fourteen MgCa2Ce2Mg8 cuboctahedra, edges with eighteen MgMg12 cuboctahedra, faces with two equivalent CeCa2Mg10 cuboctahedra, and faces with eighteen MgMg12 cuboctahedra. There are a spread of Mg–Mg bond distances ranging from 3.21–3.27 Å. In the third Mg site, Mg is bonded to two equivalent Ca, eight Mg, and two equivalent Ce atoms to form distorted MgCa2Ce2Mg8 cuboctahedra that share corners with eighteen MgMg12 cuboctahedra, edges with two equivalent CaCe2Mg10 cuboctahedra, edges with two equivalent CeCa2Mg10 cuboctahedra, edges with fourteen MgCa2Ce2Mg8 cuboctahedra, faces with two equivalent CaCe2Mg10 cuboctahedra, faces with two equivalent CeCa2Mg10 cuboctahedra, and faces with sixteen MgMg12 cuboctahedra. There are a spread of Mg–Mg bond distances ranging from 3.24–3.38 Å. There are one shorter (3.23 Å) and one longer (3.30 Å) Mg–Ce bond lengths. In the fourth Mg site, Mg is bonded to twelve Mg atoms to form MgMg12 cuboctahedra that share corners with four equivalent CaCe2Mg10 cuboctahedra, corners with four equivalent CeCa2Mg10 cuboctahedra, corners with ten MgMg12 cuboctahedra, edges with eighteen MgMg12 cuboctahedra, and faces with twenty MgMg12 cuboctahedra. There are a spread of Mg–Mg bond distances ranging from 3.19–3.35 Å. In the fifth Mg site, Mg is bonded to twelve Mg atoms to form MgMg12 cuboctahedra that share corners with four equivalent CaCe2Mg10 cuboctahedra, corners with four equivalent CeCa2Mg10 cuboctahedra, corners with ten MgMg12 cuboctahedra, edges with eighteen MgMg12 cuboctahedra, and faces with twenty MgMg12 cuboctahedra. There are a spread of Mg–Mg bond distances ranging from 3.19–3.35 Å. In the sixth Mg site, Mg is bonded to one Ca, ten Mg, and one Ce atom to form distorted MgCaCeMg10 cuboctahedra that share corners with eighteen MgCeMg11 cuboctahedra, edges with two equivalent CaCe2Mg10 cuboctahedra, edges with two equivalent CeCa2Mg10 cuboctahedra, edges with fourteen MgMg12 cuboctahedra, a faceface with one CaCe2Mg10 cuboctahedra, a faceface with one CeCa2Mg10 cuboctahedra, and faces with eighteen MgMg12 cuboctahedra. There are a spread of Mg–Mg bond distances ranging from 3.23–3.37 Å. The Mg–Ce bond length is 3.27 Å. In the seventh Mg site, Mg is bonded to one Ca, ten Mg, and one Ce atom to form distorted MgCaCeMg10 cuboctahedra that share corners with eighteen MgCaCeMg10 cuboctahedra, edges with two equivalent CaCe2Mg10 cuboctahedra, edges with two equivalent CeCa2Mg10 cuboctahedra, edges with fourteen MgMg12 cuboctahedra, a faceface with one CaCe2Mg10 cuboctahedra, a faceface with one CeCa2Mg10 cuboctahedra, and faces with eighteen MgMg12 cuboctahedra. There are a spread of Mg–Mg bond distances ranging from 3.23–3.37 Å. The Mg–Ce bond length is 3.27 Å. In the eighth Mg site, Mg is bonded to one Ca and eleven Mg atoms to form distorted MgCaMg11 cuboctahedra that share corners with eighteen MgCeMg11 cuboctahedra, edges with two equivalent CaCe2Mg10 cuboctahedra, edges with sixteen MgMg12 cuboctahedra, a faceface with one CaCe2Mg10 cuboctahedra, faces with three equivalent CeCa2Mg10 cuboctahedra, and faces with sixteen MgMg12 cuboctahedra. There are a spread of Mg–Mg bond distances ranging from 3.23–3.34 Å. In the ninth Mg site, Mg is bonded to eleven Mg and one Ce atom to form MgCeMg11 cuboctahedra that share corners with eighteen MgCeMg11 cuboctahedra, edges with two equivalent CeCa2Mg10 cuboctahedra, edges with sixteen MgMg12 cuboctahedra, a faceface with one CeCa2Mg10 cuboctahedra, faces with three equivalent CaCe2Mg10 cuboctahedra, and faces with sixteen MgMg12 cuboctahedra. There are two shorter (3.25 Å) and one longer (3.26 Å) Mg–Mg bond lengths. The Mg–Ce bond length is 3.24 Å. In the tenth Mg site, Mg is bonded to two equivalent Ca, eight Mg, and two equivalent Ce atoms to form distorted MgCa2Ce2Mg8 cuboctahedra that share corners with eighteen MgMg12 cuboctahedra, edges with two equivalent CaCe2Mg10 cuboctahedra, edges with two equivalent CeCa2Mg10 cuboctahedra, edges with fourteen MgCaCeMg10 cuboctahedra, faces with two equivalent CaCe2Mg10 cuboctahedra, faces with two equivalent CeCa2Mg10 cuboctahedra, and faces with sixteen MgCa2Ce2Mg8 cuboctahedra. Both Mg–Mg bond lengths are 3.24 Å. There are one shorter (3.23 Å) and one longer (3.30 Å) Mg–Ce bond lengths. In the eleventh Mg site, Mg is bonded to twelve Mg atoms to form MgMg12 cuboctahedra that share corners with four equivalent CaCe2Mg10 cuboctahedra, corners with four equivalent CeCa2Mg10 cuboctahedra, corners with ten MgCa2Ce2Mg8 cuboctahedra, edges with eighteen MgMg12 cuboctahedra, and faces with twenty MgMg12 cuboctahedra. There are a spread of Mg–Mg bond distances ranging from 3.19–3.25 Å. In the twelfth Mg site, Mg is bonded to twelve Mg atoms to form MgMg12 cuboctahedra that share corners with four equivalent CaCe2Mg10 cuboctahedra, corners with four equivalent CeCa2Mg10 cuboctahedra, corners with ten MgCa2Ce2Mg8 cuboctahedra, edges with eighteen MgMg12 cuboctahedra, and faces with twenty MgMg12 cuboctahedra. Both Mg–Mg bond lengths are 3.19 Å. In the thirteenth Mg site, Mg is bonded to one Ca, ten Mg, and one Ce atom to form distorted MgCaCeMg10 cuboctahedra that share corners with eighteen MgCaCeMg10 cuboctahedra, edges with two equivalent CaCe2Mg10 cuboctahedra, edges with two equivalent CeCa2Mg10 cuboctahedra, edges with fourteen MgMg12 cuboctahedra, a faceface with one CaCe2Mg10 cuboctahedra, a faceface with one CeCa2Mg10 cuboctahedra, and faces with eighteen MgMg12 cuboctahedra. The Mg–Ca bond length is 3.28 Å. There are a spread of Mg–Mg bond distances ranging from 3.21–3.24 Å. The Mg–Ce bond length is 3.27 Å. Ce is bonded to two equivalent Ca and ten Mg atoms to form CeCa2Mg10 cuboctahedra that share corners with six equivalent CeCa2Mg10 cuboctahedra, corners with twelve MgMg12 cuboctahedra, edges with two equivalent CaCe2Mg10 cuboctahedra, edges with sixteen MgCa2Ce2Mg8 cuboctahedra, faces with two equivalent CaCe2Mg10 cuboctahedra, and faces with eighteen MgMg12 cuboctahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on KCa2(SiO3)8 by Materials Project

KCa2(SiO3)8 crystallizes in the monoclinic P2_1/m space group. The structure is three-dimensional. K is bonded in a 8-coordinate geometry to eight O atoms. There are a spread of K–O bond distances ranging from 2.85–2.89 Å. There are two inequivalent Ca sites. In the first Ca site, Ca is bonded to six O atoms to form distorted CaO6 octahedra that share corners with four SiO4 tetrahedra and edges with two equivalent CaO6 octahedra. There are four shorter (2.27 Å) and two longer (2.93 Å) Ca–O bond lengths. In the second Ca site, Ca is bonded to six O atoms to form CaO6 octahedra that share corners with six SiO4 tetrahedra and edges with two equivalent CaO6 octahedra. There are four shorter (2.38 Å) and two longer (2.40 Å) Ca–O bond lengths. There are four inequivalent Si sites. In the first Si site, Si is bonded to four O atoms to form corner-sharing SiO4 tetrahedra. There are a spread of Si–O bond distances ranging from 1.61–1.64 Å. In the second Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share corners with two CaO6 octahedra and corners with three SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 47–55°. There are a spread of Si–O bond distances ranging from 1.60–1.67 Å. In the third Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share corners with two CaO6 octahedra and corners with three SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 46–55°. There are a spread of Si–O bond distances ranging from 1.60–1.67 Å. In the fourth Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share a cornercorner with one CaO6 octahedra and corners with three SiO4 tetrahedra. The corner-sharing octahedral tilt angles are 49°. There is two shorter (1.63 Å) and two longer (1.64 Å) Si–O bond length. There are thirteen inequivalent O sites. In the first O site, O is bonded in a water-like geometry to one K and one O atom. The O–O bond length is 1.29 Å. In the second O site, O is bonded in a distorted bent 120 degrees geometry to two equivalent O atoms. In the third O site, O is bonded in a bent 150 degrees geometry to two equivalent Si atoms. In the fourth O site, O is bonded in a bent 120 degrees geometry to one Ca and one O atom. The O–O bond length is 1.23 Å. In the fifth O site, O is bonded in a distorted trigonal planar geometry to two Ca and one Si atom. In the sixth O site, O is bonded in a distorted trigonal planar geometry to two Ca and one Si atom. In the seventh O site, O is bonded in a distorted bent 150 degrees geometry to one K and two Si atoms. In the eighth O site, O is bonded in a 2-coordinate geometry to one K and two Si atoms. In the ninth O site, O is bonded in a 2-coordinate geometry to one K and two Si atoms. In the tenth O site, O is bonded in a linear geometry to two Si atoms. In the eleventh O site, O is bonded in a bent 150 degrees geometry to two Si atoms. In the twelfth O site, O is bonded in a bent 150 degrees geometry to two Si atoms. In the thirteenth O site, O is bonded in a distorted bent 120 degrees geometry to one Ca and one Si atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ca11Sn3C8 by Materials Project

Ca11C8(Sn)3 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional and consists of twelve 7440-31-5 molecules and one Ca11C8 framework. In the Ca11C8 framework, there are eleven inequivalent Ca2+ sites. In the first Ca2+ site, Ca2+ is bonded in a linear geometry to two C4- atoms. There are one shorter (2.53 Å) and one longer (2.55 Å) Ca–C bond lengths. In the second Ca2+ site, Ca2+ is bonded in a distorted rectangular see-saw-like geometry to four C4- atoms. There are a spread of Ca–C bond distances ranging from 2.47–2.90 Å. In the third Ca2+ site, Ca2+ is bonded in a bent 150 degrees geometry to two C4- atoms. There are one shorter (2.53 Å) and one longer (2.56 Å) Ca–C bond lengths. In the fourth Ca2+ site, Ca2+ is bonded in a 3-coordinate geometry to three C4- atoms. There are a spread of Ca–C bond distances ranging from 2.60–2.94 Å. In the fifth Ca2+ site, Ca2+ is bonded in a distorted T-shaped geometry to three C4- atoms. There are two shorter (2.55 Å) and one longer (2.91 Å) Ca–C bond lengths. In the sixth Ca2+ site, Ca2+ is bonded in a 2-coordinate geometry to three C4- atoms. There are a spread of Ca–C bond distances ranging from 2.48–2.72 Å. In the seventh Ca2+ site, Ca2+ is bonded in a distorted hexagonal planar geometry to six C4- atoms. There are a spread of Ca–C bond distances ranging from 2.47–2.86 Å. In the eighth Ca2+ site, Ca2+ is bonded in a 4-coordinate geometry to four C4- atoms. There are a spread of Ca–C bond distances ranging from 2.44–3.00 Å. In the ninth Ca2+ site, Ca2+ is bonded in a 1-coordinate geometry to three C4- atoms. There are a spread of Ca–C bond distances ranging from 2.45–2.74 Å. In the tenth Ca2+ site, Ca2+ is bonded in a 2-coordinate geometry to five C4- atoms. There are a spread of Ca–C bond distances ranging from 2.48–2.94 Å. In the eleventh Ca2+ site, Ca2+ is bonded in a 3-coordinate geometry to three C4- atoms. There are a spread of Ca–C bond distances ranging from 2.60–2.88 Å. There are eight inequivalent C4- sites. In the first C4- site, C4- is bonded in a distorted rectangular see-saw-like geometry to five Ca2+ and one C4- atom. The C–C bond length is 1.32 Å. In the second C4- site, C4- is bonded in a 4-coordinate geometry to six Ca2+ and one C4- atom. The C–C bond length is 1.33 Å. In the third C4- site, C4- is bonded to three Ca2+ and two C4- atoms to form corner-sharing CCa3C2 trigonal bipyramids. The C–C bond length is 1.33 Å. In the fourth C4- site, C4- is bonded in a 4-coordinate geometry to six Ca2+ and one C4- atom. In the fifth C4- site, C4- is bonded to three Ca2+ and two C4- atoms to form corner-sharing CCa3C2 trigonal bipyramids. The C–C bond length is 1.33 Å. In the sixth C4- site, C4- is bonded in a 5-coordinate geometry to five Ca2+ and one C4- atom. The C–C bond length is 1.27 Å. In the seventh C4- site, C4- is bonded in a 5-coordinate geometry to four Ca2+ and one C4- atom. In the eighth C4- site, C4- is bonded in a 4-coordinate geometry to six Ca2+ and one C4- atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ca2Mg by Materials Project

Ca2Mg crystallizes in the trigonal P-3m1 space group. The structure is three-dimensional. there are two inequivalent Ca sites. In the first Ca site, Ca is bonded to twelve Ca atoms to form a mixture of edge, corner, and face-sharing CaCa12 cuboctahedra. There are six shorter (3.74 Å) and six longer (3.94 Å) Ca–Ca bond lengths. In the second Ca site, Ca is bonded to three equivalent Ca and three equivalent Mg atoms to form a mixture of distorted edge, corner, and face-sharing CaCa3Mg3 cuboctahedra. All Ca–Mg bond lengths are 3.52 Å. Mg is bonded in a 6-coordinate geometry to three equivalent Ca and three equivalent Mg atoms. All Mg–Mg bond lengths are 3.32 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ca3Mn by Materials Project

Ca3Mn is alpha bismuth trifluoride structured and crystallizes in the trigonal R-3m space group. The structure is three-dimensional. there are two inequivalent Ca sites. In the first Ca site, Ca is bonded to four equivalent Ca and four equivalent Mn atoms to form a mixture of distorted edge, face, and corner-sharing CaCa4Mn4 tetrahedra. There are one shorter (3.45 Å) and three longer (3.47 Å) Ca–Ca bond lengths. There are one shorter (3.45 Å) and three longer (3.47 Å) Ca–Mn bond lengths. In the second Ca site, Ca is bonded in a distorted body-centered cubic geometry to eight equivalent Ca atoms. Mn is bonded in a body-centered cubic geometry to eight equivalent Ca atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on SrCaB14H5O26 by Materials Project

SrCaB14H3O26H2 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional and consists of eight hydrogen molecules and one SrCaB14H3O26 framework. In the SrCaB14H3O26 framework, Sr is bonded in a 10-coordinate geometry to two H and eight O atoms. There are one shorter (2.79 Å) and one longer (2.81 Å) Sr–H bond lengths. There are a spread of Sr–O bond distances ranging from 2.48–2.96 Å. Ca is bonded in a 8-coordinate geometry to one H and seven O atoms. The Ca–H bond length is 2.73 Å. There are a spread of Ca–O bond distances ranging from 2.21–2.71 Å. There are fourteen inequivalent B sites. In the first B site, B is bonded to four O atoms to form corner-sharing BO4 tetrahedra. There are a spread of B–O bond distances ranging from 1.46–1.52 Å. In the second B site, B is bonded in a trigonal planar geometry to three O atoms. There are a spread of B–O bond distances ranging from 1.36–1.38 Å. In the third B site, B is bonded in a trigonal planar geometry to three O atoms. There are a spread of B–O bond distances ranging from 1.37–1.39 Å. In the fourth B site, B is bonded in a trigonal planar geometry to three O atoms. There is one shorter (1.37 Å) and two longer (1.38 Å) B–O bond length. In the fifth B site, B is bonded in a trigonal planar geometry to three O atoms. There is two shorter (1.37 Å) and one longer (1.38 Å) B–O bond length. In the sixth B site, B is bonded in a trigonal planar geometry to three O atoms. There is two shorter (1.37 Å) and one longer (1.38 Å) B–O bond length. In the seventh B site, B is bonded in a trigonal planar geometry to three O atoms. There are a spread of B–O bond distances ranging from 1.35–1.41 Å. In the eighth B site, B is bonded to four O atoms to form corner-sharing BO4 tetrahedra. There are a spread of B–O bond distances ranging from 1.45–1.57 Å. In the ninth B site, B is bonded in a trigonal planar geometry to three O atoms. There are a spread of B–O bond distances ranging from 1.34–1.42 Å. In the tenth B site, B is bonded to four O atoms to form corner-sharing BO4 tetrahedra. There are a spread of B–O bond distances ranging from 1.45–1.54 Å. In the eleventh B site, B is bonded to four O atoms to form corner-sharing BO4 tetrahedra. There are a spread of B–O bond distances ranging from 1.46–1.54 Å. In the twelfth B site, B is bonded to four O atoms to form corner-sharing BO4 tetrahedra. There are a spread of B–O bond distances ranging from 1.45–1.56 Å. In the thirteenth B site, B is bonded in a trigonal planar geometry to three O atoms. There is one shorter (1.37 Å) and two longer (1.38 Å) B–O bond length. In the fourteenth B site, B is bonded to four O atoms to form corner-sharing BO4 tetrahedra. There are a spread of B–O bond distances ranging from 1.44–1.52 Å. There are three inequivalent H sites. In the first H site, H is bonded in a single-bond geometry to one Sr atom. In the second H site, H is bonded in a single-bond geometry to one Ca atom. In the third H site, H is bonded in a single-bond geometry to one Sr atom. There are twenty-six inequivalent O sites. In the first O site, O is bonded in a distorted bent 120 degrees geometry to one Sr and two B atoms. In the second O site, O is bonded in a distorted bent 150 degrees geometry to one Sr and one B atom. In the third O site, O is bonded in a distorted bent 120 degrees geometry to one Ca and two B atoms. In the fourth O site, O is bonded in a distorted bent 120 degrees geometry to one Sr and two B atoms. In the fifth O site, O is bonded in a bent 120 degrees geometry to one Ca and two B atoms. In the sixth O site, O is bonded in a bent 120 degrees geometry to two B atoms. In the seventh O site, O is bonded in a trigonal planar geometry to three B atoms. In the eighth O site, O is bonded in a bent 120 degrees geometry to one Sr and two B atoms. In the ninth O site, O is bonded in a distorted bent 120 degrees geometry to one Ca and two B atoms. In the tenth O site, O is bonded in a bent 120 degrees geometry to two B atoms. In the eleventh O site, O is bonded in a bent 120 degrees geometry to one Sr and two B atoms. In the twelfth O site, O is bonded in a single-bond geometry to one B atom. In the thirteenth O site, O is bonded in a distorted bent 120 degrees geometry to one Ca and two B atoms. In the fourteenth O site, O is bonded in a bent 120 degrees geometry to two B atoms. In the fifteenth O site, O is bonded in a bent 120 degrees geometry to two B atoms. In the sixteenth O site, O is bonded in a distorted bent 120 degrees geometry to one Sr and two B atoms. In the seventeenth O site, O is bonded in a single-bond geometry to one B atom. In the eighteenth O site, O is bonded in a distorted single-bond geometry to one Sr and one B atom. In the nineteenth O site, O is bonded in a trigonal planar geometry to three B atoms. In the twentieth O site, O is bonded in a distorted bent 120 degrees geometry to one Ca and two B atoms. In the twenty-first O site, O is bonded in a distorted bent 120 degrees geometry to one Ca and two B atoms. In the twenty-second O site, O is bonded in a bent 120 degrees geometry to two B atoms. In the twenty-third O site, O is bonded in a bent 120 degrees geometry to two B atoms. In the twenty-fourth O site, O is bonded in a bent 120 degrees geometry to one Ca and one B atom. In the twenty-fifth O site, O is bonded in a distorted bent 120 degrees geometry to one Sr and two B atoms. In the twenty-sixth O site, O is bonded in a single-bond geometry to one B atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on CaO2 by Materials Project

CaO2 is Fluorite-like structured and crystallizes in the monoclinic C2 space group. The structure is three-dimensional. there are two inequivalent Ca sites. In the first Ca site, Ca is bonded in a body-centered cubic geometry to eight O atoms. There are a spread of Ca–O bond distances ranging from 2.39–2.46 Å. In the second Ca site, Ca is bonded in a body-centered cubic geometry to eight O atoms. There are a spread of Ca–O bond distances ranging from 2.38–2.46 Å. There are four inequivalent O sites. In the first O site, O is bonded to four Ca atoms to form a mixture of edge and corner-sharing OCa4 tetrahedra. In the second O site, O is bonded to four Ca atoms to form a mixture of edge and corner-sharing OCa4 tetrahedra. In the third O site, O is bonded to four Ca atoms to form a mixture of edge and corner-sharing OCa4 tetrahedra. In the fourth O site, O is bonded to four Ca atoms to form a mixture of edge and corner-sharing OCa4 tetrahedra.

36 MATERIALS SCIENCE↗
NASA NTRS2001

Calcium-stimulated autophosphorylation site of plant chimeric calcium/calmodulin-dependent protein kinase

The existence of two molecular switches regulating plant chimeric Ca(2+)/calmodulin-dependent protein kinase (CCaMK), namely the C-terminal visinin-like domain acting as Ca(2+)-sensitive molecular switch and calmodulin binding domain acting as Ca(2+)-stimulated autophosphorylation-sensitive molecular switch, has been described (Sathyanarayanan, P. V., Cremo, C. R., and Poovaiah, B. W. (2000) J. Biol. Chem. 275, 30417-30422). Here we report the identification of Ca(2+)-stimulated autophosphorylation site of CCaMK by matrix-assisted laser desorption ionization time of flight-mass spectrometry. Thr(267) was confirmed as the Ca(2+)-stimulated autophosphorylation site by post-source decay experiments and by site-directed mutagenesis. The purified T267A mutant form of CCaMK did not show Ca(2+)-stimulated autophosphorylation, autophosphorylation-dependent variable calmodulin affinity, or Ca(2+)/calmodulin stimulation of kinase activity. Sequence comparison of CCaMK from monocotyledonous plant (lily) and dicotyledonous plant (tobacco) suggests that the autophosphorylation site is conserved. This is the first identification of a phosphorylation site specifically responding to activation by second messenger system (Ca(2+) messenger system) in plants. Homology modeling of the kinase and calmodulin binding domain of CCaMK with the crystal structure of calcium/calmodulin-dependent protein kinase 1 suggests that the Ca(2+)-stimulated autophosphorylation site is located on the surface of the kinase and far from the catalytic site. Analysis of Ca(2+)-stimulated autophosphorylation with increasing concentration of CCaMK indicates the possibility that the Ca(2+)-stimulated phosphorylation occurs by an intermolecular mechanism.

Non-NASA Center↗
NASA NTRS2000

Calmodulin activation of an endoplasmic reticulum-located calcium pump involves an interaction with the N-terminal autoinhibitory domain

To investigate how calmodulin regulates a unique subfamily of Ca(2+) pumps found in plants, we examined the kinetic properties of isoform ACA2 identified in Arabidopsis. A recombinant ACA2 was expressed in a yeast K616 mutant deficient in two endogenous Ca(2+) pumps. Orthovanadate-sensitive (45)Ca(2+) transport into vesicles isolated from transformants demonstrated that ACA2 is a Ca(2+) pump. Ca(2+) pumping by the full-length protein (ACA2-1) was 4- to 10-fold lower than that of the N-terminal truncated ACA2-2 (Delta2-80), indicating that the N-terminal domain normally acts to inhibit the pump. An inhibitory sequence (IC(50) = 4 microM) was localized to a region within valine-20 to leucine-44, because a peptide corresponding to this sequence lowered the V(max) and increased the K(m) for Ca(2+) of the constitutively active ACA2-2 to values comparable to the full-length pump. The peptide also blocked the activity (IC(50) = 7 microM) of a Ca(2+) pump (AtECA1) belonging to a second family of Ca(2+) pumps. This inhibitory sequence appears to overlap with a calmodulin-binding site in ACA2, previously mapped between aspartate-19 and arginine-36 (J.F. Harper, B. Hong, I. Hwang, H.Q. Guo, R. Stoddard, J.F. Huang, M.G. Palmgren, H. Sze inverted question mark1998 J Biol Chem 273: 1099-1106). These results support a model in which the pump is kept "unactivated" by an intramolecular interaction between an autoinhibitory sequence located between residues 20 and 44 and a site in the Ca(2+) pump core that is highly conserved between different Ca(2+) pump families. Results further support a model in which activation occurs as a result of Ca(2+)-induced binding of calmodulin to a site overlapping or immediately adjacent to the autoinhibitory sequence.

NASA Program Fundamental Space Biology↗
DOE OSTI2020

Effect of Bicarbonate, Calcium, and pH on the Reactivity of As(V) and U(VI) Mixtures

Natural or anthropogenic processes can increase the concentration of uranium (U) and arsenic (As) above the maximum contaminant levels in water sources. Bicarbonate and calcium (Ca) can have major impacts on U speciation and can affect the reactivity between U and As. We therefore investigated the reactivity of aqueous U and As mixtures with bicarbonate and Ca for acidic and neutral pH conditions. In experiments performed with 1 mM U and As mixtures, 10 mM Ca, and without added bicarbonate (pCO 2 = 3.5), aqueous U decreased to <0.25 mM at pH 3 and 7. Aqueous As decreased the most at pH 3 (~0.125 mM). Experiments initiated with 0.005 mM As and U showed similar trends. X-ray spectroscopy (i.e., XAS and EDX) and diffraction indicated that U-As-Ca- and U-Ca-bearing solids resemble uranospinite [Ca(UO 2 ) 2 (AsO 4 ) 2 ·10H 2 O] and becquerelite [Ca(UO 2 ) 6 O 4 (OH) 6 ·8(H 2 O)]. These findings suggest that U-As-Ca-bearing solids formed in mixed solutions are stable at pH 3. However, the dissolution of U-As-Ca and U-Ca-bearing solids at pH 7 was observed in reactors containing 10 mM bicarbonate and Ca, suggesting a kinetic reaction of aqueous uranyl-calcium-carbonate complexation. Our study provides new insights regarding U and As mobilization for risk assessment and remediation strategies.

54 ENVIRONMENTAL SCIENCES↗
NASA NTRS2007

Step 1:Human System Integration (HSI) FY05 Pilot-Technology Interface Requirements for Collision Avoidance

This document provides definition of technology human interface requirements for Collision Avoidance (CA). This was performed through a review of CA-related, HSI requirements documents, standards, and recommended practices. Technology concepts in use by the Access 5 CA work package were considered... Beginning with the HSI high-level functional requirement for CA, and CA technology elements, HSI requirements for the interface to the pilot were identified. Results of the analysis describe (1) the information required by the pilot to have knowledge CA system status, and (2) the control capability needed by the pilot to obtain CA information and affect an avoidance maneuver. Fundamentally, these requirements provide the candidate CA technology concepts with the necessary human-related elements to make them compatible with human capabilities and limitations. The results of the analysis describe how CA operations and functions should interface with the pilot to provide the necessary CA functionality to the UA-pilot system .Requirements and guidelines for CA are partitioned into four categories: (1) General, (2) Alerting, (3) Guidance, and (4) Cockpit Display of Traffic Information. Each requirement is stated and is supported with a rationale and associated reference(s).

Source record↗
NASA NTRS2019

The Effects of High-Temperature Fractional Crystallization on Calcium Isotopic Composition

We report Ca isotope fractionation among a co-genetic suite of samples from the Mauritanian Guelb el Azib ultramafic-mafic-anorthosite complex (GAC), which represents the fractional crystallization sequence of an igneous magma chamber. We investigate how the composition of an evolving crystallizing liquid and the resultant mineralogy of co-crystallizing assemblages affects inter-phase Ca isotope fractionation. Because the GAC is an Archean metamorphosed complex, we first investigate the resistance of the Ca isotope signature to secondary hydrothermal alteration and to metamorphism. While we cannot conclude here that Ca isotopes are undisturbed at the mineral scale, we show that they are preserved at the bulk rock scale. This is adequate for our study where several samples are almost monomineralic at the bulk scale level. The δ(exp 44/40)Ca (relative to NIST standard SRM 915a) of GAC layers range from −1.53 to 1.61‰, with the earliest-formed ultramafic cumulate layer being isotopically heaviest and the later, more felsic layers being isotopically lighter. For the first time, we show that plagioclase is much more enriched in light Ca isotopes compared to olivine and (Ca-) pyroxene. Monte Carlo simulations suggest that Ca isotopes are fractionated among co-existing silicate minerals during fractional crystallization, possibly in relation with the residual liquid composition. In qualitative agreement with computational models based on first principles lattice dynamics, we observe that Ca isotope fractionation is mineralogically controlled and importantly, that the degree of fractionation can vary according to the CaO composition of the residual liquid. While previous studies have aimed to understand partial melting as a source of Ca isotope fractionation, our results suggest that fractional crystallization is also a source of Ca isotope variability among co-genetic samples.

Maria C. Valdes↗