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DOE OSTI2020

Materials Data on Ca3Mg by Materials Project

MgCa3 crystallizes in the orthorhombic Imm2 space group. The structure is three-dimensional. there are two inequivalent Ca sites. In the first Ca site, Ca is bonded to eight Ca and four equivalent Mg atoms to form a mixture of distorted face, edge, and corner-sharing CaCa8Mg4 cuboctahedra. There are a spread of Ca–Ca bond distances ranging from 3.69–3.87 Å. There are two shorter (3.63 Å) and two longer (3.80 Å) Ca–Mg bond lengths. In the second Ca site, Ca is bonded in a 12-coordinate geometry to three equivalent Ca and two equivalent Mg atoms. Both Ca–Mg bond lengths are 3.59 Å. Mg is bonded in a 8-coordinate geometry to eight Ca atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ca2Mg by Materials Project

Ca2Mg crystallizes in the hexagonal P-62m space group. The structure is three-dimensional. there are two inequivalent Ca sites. In the first Ca site, Ca is bonded to eight Ca and four equivalent Mg atoms to form a mixture of distorted edge, face, and corner-sharing CaCa8Mg4 cuboctahedra. There are a spread of Ca–Ca bond distances ranging from 3.61–3.83 Å. All Ca–Mg bond lengths are 3.64 Å. In the second Ca site, Ca is bonded to six equivalent Ca and six equivalent Mg atoms to form a mixture of edge and face-sharing CaCa6Mg6 cuboctahedra. All Ca–Mg bond lengths are 3.68 Å. Mg is bonded in a 9-coordinate geometry to nine Ca atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ca4Tl3O9 by Materials Project

Ca4Tl3O9 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. there are two inequivalent Ca sites. In the first Ca site, Ca is bonded in a 7-coordinate geometry to seven O atoms. There are a spread of Ca–O bond distances ranging from 2.32–2.81 Å. In the second Ca site, Ca is bonded to six O atoms to form CaO6 octahedra that share corners with three TlO6 octahedra, edges with three equivalent TlO6 octahedra, and edges with four equivalent CaO6 octahedra. The corner-sharing octahedra tilt angles range from 7–62°. There are a spread of Ca–O bond distances ranging from 2.27–2.43 Å. There are two inequivalent Tl sites. In the first Tl site, Tl is bonded to six O atoms to form TlO6 octahedra that share a cornercorner with one CaO6 octahedra, corners with two equivalent TlO6 octahedra, and edges with five equivalent TlO6 octahedra. The corner-sharing octahedra tilt angles range from 0–62°. There are a spread of Tl–O bond distances ranging from 2.11–2.44 Å. In the second Tl site, Tl is bonded to six O atoms to form TlO6 octahedra that share corners with four equivalent CaO6 octahedra, edges with two equivalent TlO6 octahedra, and edges with six equivalent CaO6 octahedra. The corner-sharing octahedral tilt angles are 7°. There are two shorter (2.22 Å) and four longer (2.39 Å) Tl–O bond lengths. There are five inequivalent O sites. In the first O site, O is bonded to two equivalent Ca and three equivalent Tl atoms to form distorted OCa2Tl3 trigonal bipyramids that share corners with two equivalent OCa2Tl4 octahedra, corners with five equivalent OCa3Tl tetrahedra, corners with two equivalent OCa4Tl trigonal bipyramids, edges with three equivalent OCa2Tl4 octahedra, an edgeedge with one OCa3Tl tetrahedra, and edges with five OCa4Tl trigonal bipyramids. The corner-sharing octahedral tilt angles are 8°. In the second O site, O is bonded to three equivalent Ca and two equivalent Tl atoms to form OCa3Tl2 square pyramids that share corners with two equivalent OCa3Tl2 square pyramids, corners with three equivalent OCa3Tl tetrahedra, corners with four equivalent OCa4Tl trigonal bipyramids, edges with five equivalent OCa3Tl2 square pyramids, and edges with three equivalent OCa4Tl trigonal bipyramids. In the third O site, O is bonded to three Ca and one Tl atom to form OCa3Tl tetrahedra that share corners with three equivalent OCa3Tl2 square pyramids, corners with two equivalent OCa3Tl tetrahedra, corners with nine OCa4Tl trigonal bipyramids, edges with two equivalent OCa2Tl4 octahedra, and edges with two OCa4Tl trigonal bipyramids. In the fourth O site, O is bonded to four Ca and one Tl atom to form distorted OCa4Tl trigonal bipyramids that share corners with two equivalent OCa2Tl4 octahedra, corners with four equivalent OCa3Tl2 square pyramids, corners with four equivalent OCa3Tl tetrahedra, corners with three OCa2Tl3 trigonal bipyramids, edges with three equivalent OCa3Tl2 square pyramids, an edgeedge with one OCa3Tl tetrahedra, and edges with three OCa4Tl trigonal bipyramids. The corner-sharing octahedral tilt angles are 44°. In the fifth O site, O is bonded to two equivalent Ca and four equivalent Tl atoms to form OCa2Tl4 octahedra that share corners with eight OCa4Tl trigonal bipyramids, edges with two equivalent OCa2Tl4 octahedra, edges with four equivalent OCa3Tl tetrahedra, and edges with six equivalent OCa2Tl3 trigonal bipyramids.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ca3Sm by Materials Project

Ca3Sm is alpha bismuth trifluoride structured and crystallizes in the cubic Fm-3m 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 Ca and four equivalent Sm atoms. All Ca–Ca bond lengths are 3.69 Å. All Ca–Sm bond lengths are 3.69 Å. In the second Ca site, Ca is bonded in a 8-coordinate geometry to eight equivalent Ca and six equivalent Sm atoms. All Ca–Sm bond lengths are 4.26 Å. Sm is bonded in a distorted body-centered cubic geometry to fourteen Ca atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ca3V by Materials Project

Ca3V is Uranium Silicide-like structured and crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. there are two inequivalent Ca sites. In the first Ca site, Ca is bonded to eight Ca and four equivalent V atoms to form distorted CaCa8V4 cuboctahedra that share corners with twelve equivalent CaCa8V4 cuboctahedra, edges with eight equivalent VCa12 cuboctahedra, edges with sixteen CaCa8V4 cuboctahedra, faces with four equivalent VCa12 cuboctahedra, and faces with fourteen CaCa8V4 cuboctahedra. There are four shorter (3.59 Å) and four longer (3.61 Å) Ca–Ca bond lengths. All Ca–V bond lengths are 3.61 Å. In the second Ca site, Ca is bonded to eight equivalent Ca and four equivalent V atoms to form distorted CaCa8V4 cuboctahedra that share corners with four equivalent CaCa8V4 cuboctahedra, corners with eight equivalent VCa12 cuboctahedra, edges with twenty-four CaCa8V4 cuboctahedra, faces with six equivalent VCa12 cuboctahedra, and faces with twelve CaCa8V4 cuboctahedra. All Ca–V bond lengths are 3.59 Å. V is bonded to twelve Ca atoms to form VCa12 cuboctahedra that share corners with four equivalent VCa12 cuboctahedra, corners with eight equivalent CaCa8V4 cuboctahedra, edges with eight equivalent VCa12 cuboctahedra, edges with sixteen equivalent CaCa8V4 cuboctahedra, faces with four equivalent VCa12 cuboctahedra, and faces with fourteen CaCa8V4 cuboctahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ca2S2O9 by Materials Project

Ca2S2O9 crystallizes in the trigonal P3_121 space group. The structure is three-dimensional. there are two inequivalent Ca sites. In the first Ca site, Ca is bonded in a 8-coordinate geometry to eight O atoms. There are a spread of Ca–O bond distances ranging from 2.42–2.67 Å. In the second Ca site, Ca is bonded in a 9-coordinate geometry to nine O atoms. There are a spread of Ca–O bond distances ranging from 2.43–2.63 Å. S is bonded in a tetrahedral geometry to four O atoms. There are a spread of S–O bond distances ranging from 1.48–1.50 Å. There are five inequivalent O sites. In the first O site, O is bonded in a 1-coordinate geometry to two Ca and one S atom. In the second O site, O is bonded in a single-bond geometry to one Ca atom. In the third O site, O is bonded in a 1-coordinate geometry to two Ca and one S atom. In the fourth O site, O is bonded in a 1-coordinate geometry to two Ca and one S atom. In the fifth O site, O is bonded in a 1-coordinate geometry to two Ca and one S atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ca21(Zn2Sb9)2 by Materials Project

Ca21Zn4Sb18 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. there are twelve inequivalent Ca2+ sites. In the first Ca2+ site, Ca2+ is bonded to six Sb+2.78- atoms to form distorted CaSb6 octahedra that share corners with eight CaSb6 octahedra, corners with two CaSb7 pentagonal bipyramids, corners with two ZnSb4 tetrahedra, edges with four CaSb6 octahedra, edges with two ZnSb4 tetrahedra, faces with two CaSb6 octahedra, and a faceface with one CaSb7 pentagonal bipyramid. The corner-sharing octahedra tilt angles range from 33–61°. There are a spread of Ca–Sb bond distances ranging from 3.05–3.36 Å. In the second Ca2+ site, Ca2+ is bonded to six Sb+2.78- atoms to form distorted CaSb6 octahedra that share corners with nine CaSb6 octahedra, corners with two CaSb7 pentagonal bipyramids, corners with two ZnSb4 tetrahedra, edges with three CaSb6 octahedra, an edgeedge with one ZnSb4 tetrahedra, faces with three CaSb6 octahedra, a faceface with one CaSb7 pentagonal bipyramid, and a faceface with one ZnSb4 tetrahedra. The corner-sharing octahedra tilt angles range from 33–53°. There are a spread of Ca–Sb bond distances ranging from 3.14–3.47 Å. In the third Ca2+ site, Ca2+ is bonded in a 6-coordinate geometry to six Sb+2.78- atoms. There are a spread of Ca–Sb bond distances ranging from 3.13–3.76 Å. In the fourth Ca2+ site, Ca2+ is bonded in a 7-coordinate geometry to seven Sb+2.78- atoms. There are a spread of Ca–Sb bond distances ranging from 3.12–3.87 Å. In the fifth Ca2+ site, Ca2+ is bonded to six Sb+2.78- atoms to form CaSb6 octahedra that share corners with ten CaSb6 octahedra, a cornercorner with one CaSb7 pentagonal bipyramid, corners with three ZnSb4 tetrahedra, edges with two equivalent CaSb6 octahedra, faces with four CaSb6 octahedra, and faces with two CaSb7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 31–61°. There are a spread of Ca–Sb bond distances ranging from 3.12–3.38 Å. In the sixth Ca2+ site, Ca2+ is bonded to six Sb+2.78- atoms to form distorted CaSb6 octahedra that share corners with nine CaSb6 octahedra, corners with four CaSb7 pentagonal bipyramids, a cornercorner with one ZnSb4 tetrahedra, edges with four CaSb6 octahedra, an edgeedge with one ZnSb4 tetrahedra, faces with two CaSb6 octahedra, a faceface with one CaSb7 pentagonal bipyramid, and a faceface with one ZnSb4 tetrahedra. The corner-sharing octahedra tilt angles range from 32–75°. There are a spread of Ca–Sb bond distances ranging from 3.08–3.64 Å. In the seventh Ca2+ site, Ca2+ is bonded to six Sb+2.78- atoms to form distorted CaSb6 octahedra that share corners with eight CaSb6 octahedra, corners with two CaSb7 pentagonal bipyramids, corners with four ZnSb4 tetrahedra, edges with three CaSb6 octahedra, an edgeedge with one ZnSb4 tetrahedra, faces with three CaSb6 octahedra, and a faceface with one CaSb7 pentagonal bipyramid. The corner-sharing octahedra tilt angles range from 34–71°. There are a spread of Ca–Sb bond distances ranging from 3.22–3.52 Å. In the eighth Ca2+ site, Ca2+ is bonded to six Sb+2.78- atoms to form distorted CaSb6 octahedra that share corners with eight CaSb6 octahedra, a cornercorner with one CaSb7 pentagonal bipyramid, corners with three ZnSb4 tetrahedra, edges with four CaSb6 octahedra, an edgeedge with one ZnSb4 tetrahedra, faces with two CaSb6 octahedra, and faces with two CaSb7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 35–51°. There are a spread of Ca–Sb bond distances ranging from 3.11–3.47 Å. In the ninth Ca2+ site, Ca2+ is bonded to six Sb+2.78- atoms to form distorted CaSb6 octahedra that share corners with nine CaSb6 octahedra, corners with three CaSb7 pentagonal bipyramids, a cornercorner with one ZnSb4 tetrahedra, edges with three CaSb6 octahedra, an edgeedge with one ZnSb4 tetrahedra, faces with four CaSb6 octahedra, and faces with two CaSb7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 31–75°. There are a spread of Ca–Sb bond distances ranging from 3.10–3.40 Å. In the tenth Ca2+ site, Ca2+ is bonded to seven Sb+2.78- atoms to form distorted CaSb7 pentagonal bipyramids that share corners with twelve CaSb6 octahedra, a cornercorner with one CaSb7 pentagonal bipyramid, corners with two ZnSb4 tetrahedra, edges with two CaSb7 pentagonal bipyramids, faces with six CaSb6 octahedra, and faces with two equivalent ZnSb4 tetrahedra. The corner-sharing octahedra tilt angles range from 38–56°. There are a spread of Ca–Sb bond distances ranging from 3.28–3.59 Å. In the eleventh Ca2+ site, Ca2+ is bonded to seven Sb+2.78- atoms to form CaSb7 pentagonal bipyramids that share corners with ten CaSb6 octahedra, a cornercorner with one CaSb7 pentagonal bipyramid, a cornercorner with one ZnSb4 tetrahedra, edges with two CaSb7 pentagonal bipyramids, an edgeedge with one ZnSb4 tetrahedra, faces with six CaSb6 octahedra, and faces with two equivalent ZnSb4 tetrahedra. The corner-sharing octahedra tilt angles range from 38–53°. There are a spread of Ca–Sb bond distances ranging from 3.31–3.61 Å. In the twelfth Ca2+ site, Ca2+ is bonded to seven Sb+2.78- atoms to form distorted CaSb7 pentagonal bipyramids that share corners with eight CaSb6 octahedra, corners with two CaSb7 pentagonal bipyramids, corners with two equivalent ZnSb4 tetrahedra, edges with two CaSb7 pentagonal bipyramids, an edgeedge with one ZnSb4 tetrahedra, and faces with eight CaSb6 octahedra. The corner-sharing octahedra tilt angles range from 31–45°. There are a spread of Ca–Sb bond distances ranging from 3.06–3.73 Å. There are three inequivalent Zn2+ sites. In the first Zn2+ site, Zn2+ is bonded to four Sb+2.78- atoms to form ZnSb4 tetrahedra that share corners with eight CaSb6 octahedra, a cornercorner with one CaSb7 pentagonal bipyramid, a cornercorner with one ZnSb4 tetrahedra, edges with five CaSb6 octahedra, an edgeedge with one ZnSb4 tetrahedra, and faces with two CaSb7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 33–57°. There are a spread of Zn–Sb bond distances ranging from 2.74–2.86 Å. In the second Zn2+ site, Zn2+ is bonded to four Sb+2.78- atoms to form ZnSb4 tetrahedra that share corners with eight CaSb6 octahedra, a cornercorner with one CaSb7 pentagonal bipyramid, corners with two equivalent ZnSb4 tetrahedra, edges with two equivalent CaSb6 octahedra, an edgeedge with one CaSb7 pentagonal bipyramid, an edgeedge with one ZnSb4 tetrahedra, and faces with two equivalent CaSb6 octahedra. The corner-sharing octahedra tilt angles range from 44–96°. There are a spread of Zn–Sb bond distances ranging from 2.74–2.79 Å. In the third Zn2+ site, Zn2+ is bonded to four Sb+2.78- atoms to form ZnSb4 tetrahedra that share corners with eight CaSb6 octahedra, corners with two CaSb7 pentagonal bipyramids, edges with two equivalent CaSb6 octahedra, an edgeedge with one CaSb7 pentagonal bipyramid, an edgeedge with one ZnSb4 tetrahedra, and faces with two equivalent CaSb6 octahedra. The corner-sharing octahedra tilt angles range from 39–61°. There are two shorter (2.79 Å) and two longer (2.81 Å) Zn–Sb bond lengths. There are fourteen inequivalent Sb+2.78- sites. In the first Sb+2.78- site, Sb+2.78- is bonded in a 9-coordinate geometry to seven Ca2+ and two equivalent Zn2+ atoms. In the second Sb+2.78- site, Sb+2.78- is bonded in a 9-coordinate geometry to eight Ca2+ and one Zn2+ atom. In the third Sb+2.78- site, Sb+2.78- is bonded in a 8-coordinate geometry to eight Ca2+ atoms. In the fourth Sb+2.78- site, Sb+2.78- is bonded in a 8-coordinate geometry to eight Ca2+ atoms. In the fifth Sb+2.78- site, Sb+2.78- is bonded in a 2-coordinate geometry to seven Ca2+ and one Sb+2.78- atom. The Sb–Sb bond length is 2.89 Å. In the sixth Sb+2.78- site, Sb+2.78- is bonded in a 7-coordinate geometry to five Ca2+, one Zn2+, and one Sb+2.78- atom. The Sb–Sb bond length is 2.88 Å. In the seventh Sb+2.78- site, Sb+2.78- is bonded in a 2-coordinate geometry to eight Ca2+ and one Sb+2.78- atom. The Sb–Sb bond length is 2.97 Å. In the eighth Sb+2.78- site, Sb+2.78- is bonded in a 9-coordinate geometry to eight Ca2+ and one Sb+2.78- atom. The Sb–Sb bond length is 2.97 Å. In the ninth Sb+2.78- site, Sb+2.78- is bonded in a 8-coordinate geometry to eight Ca2+ atoms. In the tenth Sb+2.78- site, Sb+2.78- is bonded in a 9-coordinate geometry to eight Ca2+ and one Zn2+ atom. In the eleventh Sb+2.78- site, Sb+2.78- is bonded in a 8-coordinate geometry to seven Ca2+ and one Zn2+ atom. In the twelfth Sb+2.78- site, Sb+2.78- is bonded in a 8-coordinate geometry to six Ca2+ and two Zn2+ atoms. In the thirteenth Sb+2.78- site, Sb+2.78- is bonded in a 9-coordinate geometry to six Ca2+ and three Zn2+ atoms. In the fourteenth Sb+2.78- site, Sb+2.78- is bonded in a 9-coordinate geometry to eight Ca2+ and one Zn2+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ca3Nd by Materials Project

Ca3Nd is alpha bismuth trifluoride structured and crystallizes in the cubic Fm-3m 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 four equivalent Ca and four equivalent Nd atoms. All Ca–Ca bond lengths are 3.70 Å. All Ca–Nd bond lengths are 3.70 Å. In the second Ca site, Ca is bonded in a 8-coordinate geometry to eight equivalent Ca and six equivalent Nd atoms. All Ca–Nd bond lengths are 4.27 Å. Nd is bonded in a distorted body-centered cubic geometry to fourteen Ca atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ca3Ac by Materials Project

Ca3Ac is alpha bismuth trifluoride structured and crystallizes in the cubic Fm-3m 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 four equivalent Ca and four equivalent Ac atoms. All Ca–Ca bond lengths are 3.80 Å. All Ca–Ac bond lengths are 3.80 Å. In the second Ca site, Ca is bonded in a 8-coordinate geometry to eight equivalent Ca and six equivalent Ac atoms. All Ca–Ac bond lengths are 4.38 Å. Ac is bonded in a distorted body-centered cubic geometry to fourteen Ca atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ca3Os by Materials Project

Ca3Os is alpha bismuth trifluoride structured and crystallizes in the cubic Fm-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 Os atoms to form a mixture of distorted corner, edge, and face-sharing CaCa4Os4 tetrahedra. All Ca–Ca bond lengths are 3.19 Å. All Ca–Os bond lengths are 3.19 Å. In the second Ca site, Ca is bonded in a 8-coordinate geometry to eight equivalent Ca and six equivalent Os atoms. All Ca–Os bond lengths are 3.69 Å. Os is bonded in a distorted body-centered cubic geometry to fourteen Ca atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ca21(Zn2As9)2 by Materials Project

Ca21Zn4As18 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. there are twelve inequivalent Ca2+ sites. In the first Ca2+ site, Ca2+ is bonded to six As+2.78- atoms to form distorted CaAs6 octahedra that share corners with seven CaAs6 octahedra, a cornercorner with one CaAs7 pentagonal bipyramid, corners with two ZnAs4 tetrahedra, edges with three CaAs6 octahedra, edges with two ZnAs4 tetrahedra, faces with two CaAs6 octahedra, and a faceface with one CaAs7 pentagonal bipyramid. The corner-sharing octahedra tilt angles range from 34–60°. There are a spread of Ca–As bond distances ranging from 2.90–3.17 Å. In the second Ca2+ site, Ca2+ is bonded to six As+2.78- atoms to form distorted CaAs6 octahedra that share corners with eight CaAs6 octahedra, a cornercorner with one CaAs7 pentagonal bipyramid, corners with two ZnAs4 tetrahedra, edges with two CaAs6 octahedra, an edgeedge with one ZnAs4 tetrahedra, faces with three CaAs6 octahedra, a faceface with one CaAs7 pentagonal bipyramid, and a faceface with one ZnAs4 tetrahedra. The corner-sharing octahedra tilt angles range from 35–52°. There are a spread of Ca–As bond distances ranging from 2.97–3.26 Å. In the third Ca2+ site, Ca2+ is bonded in a 6-coordinate geometry to six As+2.78- atoms. There are a spread of Ca–As bond distances ranging from 2.92–3.59 Å. In the fourth Ca2+ site, Ca2+ is bonded in a 7-coordinate geometry to six As+2.78- atoms. There are a spread of Ca–As bond distances ranging from 2.91–3.52 Å. In the fifth Ca2+ site, Ca2+ is bonded to six As+2.78- atoms to form CaAs6 octahedra that share corners with eight CaAs6 octahedra, a cornercorner with one CaAs7 pentagonal bipyramid, corners with three ZnAs4 tetrahedra, edges with two equivalent CaAs6 octahedra, faces with three CaAs6 octahedra, and a faceface with one CaAs7 pentagonal bipyramid. The corner-sharing octahedra tilt angles range from 34–60°. There are a spread of Ca–As bond distances ranging from 2.97–3.19 Å. In the sixth Ca2+ site, Ca2+ is bonded in a 6-coordinate geometry to six As+2.78- atoms. There are a spread of Ca–As bond distances ranging from 2.87–3.53 Å. In the seventh Ca2+ site, Ca2+ is bonded to six As+2.78- atoms to form distorted CaAs6 octahedra that share corners with six CaAs6 octahedra, a cornercorner with one CaAs7 pentagonal bipyramid, corners with four ZnAs4 tetrahedra, edges with three CaAs6 octahedra, an edgeedge with one ZnAs4 tetrahedra, faces with two CaAs6 octahedra, and a faceface with one CaAs7 pentagonal bipyramid. The corner-sharing octahedra tilt angles range from 36–73°. There are a spread of Ca–As bond distances ranging from 3.03–3.42 Å. In the eighth Ca2+ site, Ca2+ is bonded to six As+2.78- atoms to form distorted CaAs6 octahedra that share corners with seven CaAs6 octahedra, a cornercorner with one CaAs7 pentagonal bipyramid, corners with three ZnAs4 tetrahedra, edges with three CaAs6 octahedra, an edgeedge with one ZnAs4 tetrahedra, faces with two CaAs6 octahedra, and a faceface with one CaAs7 pentagonal bipyramid. The corner-sharing octahedra tilt angles range from 35–52°. There are a spread of Ca–As bond distances ranging from 2.91–3.34 Å. In the ninth Ca2+ site, Ca2+ is bonded to six As+2.78- atoms to form distorted CaAs6 octahedra that share corners with seven CaAs6 octahedra, corners with two CaAs7 pentagonal bipyramids, a cornercorner with one ZnAs4 tetrahedra, edges with three CaAs6 octahedra, an edgeedge with one ZnAs4 tetrahedra, faces with four CaAs6 octahedra, and a faceface with one CaAs7 pentagonal bipyramid. The corner-sharing octahedra tilt angles range from 34–50°. There are a spread of Ca–As bond distances ranging from 2.91–3.18 Å. In the tenth Ca2+ site, Ca2+ is bonded to seven As+2.78- atoms to form distorted CaAs7 pentagonal bipyramids that share corners with eight CaAs6 octahedra, corners with two ZnAs4 tetrahedra, an edgeedge with one CaAs7 pentagonal bipyramid, faces with six CaAs6 octahedra, and faces with two equivalent ZnAs4 tetrahedra. The corner-sharing octahedra tilt angles range from 39–55°. There are a spread of Ca–As bond distances ranging from 3.08–3.43 Å. In the eleventh Ca2+ site, Ca2+ is bonded to seven As+2.78- atoms to form CaAs7 pentagonal bipyramids that share corners with six CaAs6 octahedra, a cornercorner with one ZnAs4 tetrahedra, an edgeedge with one CaAs7 pentagonal bipyramid, an edgeedge with one ZnAs4 tetrahedra, faces with six CaAs6 octahedra, and faces with two equivalent ZnAs4 tetrahedra. The corner-sharing octahedra tilt angles range from 38–50°. There are a spread of Ca–As bond distances ranging from 3.05–3.46 Å. In the twelfth Ca2+ site, Ca2+ is bonded in a 7-coordinate geometry to seven As+2.78- atoms. There are a spread of Ca–As bond distances ranging from 2.87–3.66 Å. There are three inequivalent Zn2+ sites. In the first Zn2+ site, Zn2+ is bonded to four As+2.78- atoms to form ZnAs4 tetrahedra that share corners with eight CaAs6 octahedra, a cornercorner with one ZnAs4 tetrahedra, edges with four CaAs6 octahedra, an edgeedge with one ZnAs4 tetrahedra, and faces with two CaAs7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 36–56°. There are a spread of Zn–As bond distances ranging from 2.56–2.71 Å. In the second Zn2+ site, Zn2+ is bonded to four As+2.78- atoms to form ZnAs4 tetrahedra that share corners with six CaAs6 octahedra, a cornercorner with one CaAs7 pentagonal bipyramid, corners with two equivalent ZnAs4 tetrahedra, edges with two equivalent CaAs6 octahedra, an edgeedge with one CaAs7 pentagonal bipyramid, an edgeedge with one ZnAs4 tetrahedra, and faces with two equivalent CaAs6 octahedra. The corner-sharing octahedra tilt angles range from 43–96°. There are a spread of Zn–As bond distances ranging from 2.54–2.62 Å. In the third Zn2+ site, Zn2+ is bonded to four As+2.78- atoms to form ZnAs4 tetrahedra that share corners with eight CaAs6 octahedra, corners with two CaAs7 pentagonal bipyramids, edges with two equivalent CaAs6 octahedra, and an edgeedge with one ZnAs4 tetrahedra. The corner-sharing octahedra tilt angles range from 38–61°. All Zn–As bond lengths are 2.61 Å. There are fourteen inequivalent As+2.78- sites. In the first As+2.78- site, As+2.78- is bonded in a 9-coordinate geometry to seven Ca2+ and two equivalent Zn2+ atoms. In the second As+2.78- site, As+2.78- is bonded in a 9-coordinate geometry to eight Ca2+ and one Zn2+ atom. In the third As+2.78- site, As+2.78- is bonded in a 8-coordinate geometry to eight Ca2+ atoms. In the fourth As+2.78- site, As+2.78- is bonded in a 8-coordinate geometry to eight Ca2+ atoms. In the fifth As+2.78- site, As+2.78- is bonded in a 8-coordinate geometry to seven Ca2+ and one As+2.78- atom. The As–As bond length is 2.50 Å. In the sixth As+2.78- site, As+2.78- is bonded in a 7-coordinate geometry to five Ca2+, one Zn2+, and one As+2.78- atom. The As–As bond length is 2.51 Å. In the seventh As+2.78- site, As+2.78- is bonded in a 9-coordinate geometry to eight Ca2+ and one As+2.78- atom. The As–As bond length is 2.55 Å. In the eighth As+2.78- site, As+2.78- is bonded in a 9-coordinate geometry to eight Ca2+ and one As+2.78- atom. The As–As bond length is 2.57 Å. In the ninth As+2.78- site, As+2.78- is bonded in a 8-coordinate geometry to eight Ca2+ atoms. In the tenth As+2.78- site, As+2.78- is bonded in a 9-coordinate geometry to seven Ca2+ and one Zn2+ atom. In the eleventh As+2.78- site, As+2.78- is bonded in a 8-coordinate geometry to seven Ca2+ and one Zn2+ atom. In the twelfth As+2.78- site, As+2.78- is bonded in a 8-coordinate geometry to six Ca2+ and two Zn2+ atoms. In the thirteenth As+2.78- site, As+2.78- is bonded in a 9-coordinate geometry to six Ca2+ and three Zn2+ atoms. In the fourteenth As+2.78- site, As+2.78- is bonded in a 9-coordinate geometry to eight Ca2+ and one Zn2+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2024

Evaluating Material Design Principles for Calcium-Ion Mobility in Intercalation Cathodes

Multivalent-ion batteries offer an alternative to Li-based technologies, with the potential for greater sustainability, improved safety, and higher energy density, primarily due to their rechargeable system featuring a passivating metal anode. Although a system based on the Ca 2+ /Ca couple is particularly attractive given the low electrochemical plating potential of Ca 2+ , the remaining challenge for a viable rechargeable Ca battery is to identify Ca cathodes with fast ion transport. In this work, a high-throughput computational pipeline is adapted to (1) discover novel Ca cathodes in a largely unexplored space of empty intercalation hosts and (2) develop material design rules for Ca-ion mobility. One candidate from the screening, W 2 O 3 (PO 4 ) 2 , is confirmed to have a low Nudged Elastic Band (NEB) barrier of 168 meV within a one-dimensional (1D) ion percolation topology. This candidate is subsequently synthesized and electrochemically tested, achieving reversible Ca cycling with a capacity of 25 mA h/g. To further accelerate the screening for promising Ca intercalation electrodes, machine learning (ML) Random Forest (RF) and Extreme Gradient Boosting (XGB) classification models are created with local environment descriptors based on a large, structurally and chemically diverse dataset of minimum energy pathways, spanning over 5,000 density functional theory (DFT) site energy calculations. Accuracies of 92% are achieved, material design metrics are quantified, ML force-fields are leveraged in an accelerated iteration of the screening, and a total of 27 novel Ca cathode materials are highlighted for further investigation.

25 ENERGY STORAGE↗
NASA NTRS1995

Chimeric Plant Calcium/Calmodulin-Dependent Protein Kinase Gene with a Neural Visinin-Like Calcium-Binding Domain

Calcium, a universal second messenger, regulates diverse cellular processes in eukaryotes. Ca-2(+) and Ca-2(+)/calmodulin-regulated protein phosphorylation play a pivotal role in amplifying and diversifying the action of Ca-2(+)- mediated signals. A chimeric Ca-2(+)/calmodulin-dependent protein kinase (CCaMK) gene with a visinin-like Ca-2(+)- binding domain was cloned and characterized from lily. The cDNA clone contains an open reading frame coding for a protein of 520 amino acids. The predicted structure of CCaMK contains a catalytic domain followed by two regulatory domains, a calmodulin-binding domain and a visinin-like Ca-2(+)-binding domain. The amino-terminal region of CCaMK contains all 11 conserved subdomains characteristic of serine/threonine protein kinases. The calmodulin-binding region of CCaMK has high homology (79%) to alpha subunit of mammalian Ca-2(+)/calmodulin-dependent protein kinase. The calmodulin-binding region is fused to a neural visinin-like domain that contains three Ca-2(+)-binding EF-hand motifs and a biotin-binding site. The Escherichia coli-expressed protein (approx. 56 kDa) binds calmodulin in a Ca-2(+)-dependent manner. Furthermore, Ca-45-binding assays revealed that CCaMK directly binds Ca-2(+). The CCaMK gene is preferentially expressed in developing anthers. Southern blot analysis revealed that CCaMK is encoded by a single gene. The structural features of the gene suggest that it has multiple regulatory controls and could play a unique role in Ca-2(+) signaling in plants.

Patil, Shameekumar↗
NASA NTRS2001

Extracellular calcium sensing and extracellular calcium signaling

The cloning of a G protein-coupled extracellular Ca(2+) (Ca(o)(2+))-sensing receptor (CaR) has elucidated the molecular basis for many of the previously recognized effects of Ca(o)(2+) on tissues that maintain systemic Ca(o)(2+) homeostasis, especially parathyroid chief cells and several cells in the kidney. The availability of the cloned CaR enabled the development of DNA and antibody probes for identifying the CaR's mRNA and protein, respectively, within these and other tissues. It also permitted the identification of human diseases resulting from inactivating or activating mutations of the CaR gene and the subsequent generation of mice with targeted disruption of the CaR gene. The characteristic alterations in parathyroid and renal function in these patients and in the mice with "knockout" of the CaR gene have provided valuable information on the CaR's physiological roles in these tissues participating in mineral ion homeostasis. Nevertheless, relatively little is known about how the CaR regulates other tissues involved in systemic Ca(o)(2+) homeostasis, particularly bone and intestine. Moreover, there is evidence that additional Ca(o)(2+) sensors may exist in bone cells that mediate some or even all of the known effects of Ca(o)(2+) on these cells. Even more remains to be learned about the CaR's function in the rapidly growing list of cells that express it but are uninvolved in systemic Ca(o)(2+) metabolism. Available data suggest that the receptor serves numerous roles outside of systemic mineral ion homeostasis, ranging from the regulation of hormonal secretion and the activities of various ion channels to the longer term control of gene expression, programmed cell death (apoptosis), and cellular proliferation. In some cases, the CaR on these "nonhomeostatic" cells responds to local changes in Ca(o)(2+) taking place within compartments of the extracellular fluid (ECF) that communicate with the outside environment (e.g., the gastrointestinal tract). In others, localized changes in Ca(o)(2+) within the ECF can originate from several mechanisms, including fluxes of calcium ions into or out of cellular or extracellular stores or across epithelium that absorb or secrete Ca(2+). In any event, the CaR and other receptors/sensors for Ca(o)(2+) and probably for other extracellular ions represent versatile regulators of numerous cellular functions and may serve as important therapeutic targets.

Review↗
NASA NTRS1999

Intracellular Ca2+ transients in mouse soleus muscle after hindlimb unloading and reloading

The objective of this study was to determine whether altered intracellular Ca(2+) handling contributes to the specific force loss in the soleus muscle after unloading and/or subsequent reloading of mouse hindlimbs. Three groups of female ICR mice were studied: 1) unloaded mice (n = 11) that were hindlimb suspended for 14 days, 2) reloaded mice (n = 10) that were returned to their cages for 1 day after 14 days of hindlimb suspension, and 3) control mice (n = 10) that had normal cage activity. Maximum isometric tetanic force (P(o)) was determined in the soleus muscle from the left hindlimb, and resting free cytosolic Ca(2+) concentration ([Ca(2+)](i)), tetanic [Ca(2+)](i), and 4-chloro-m-cresol-induced [Ca(2+)](i) were measured in the contralateral soleus muscle by confocal laser scanning microscopy. Unloading and reloading increased resting [Ca(2+)](i) above control by 36% and 24%, respectively. Although unloading reduced P(o) and specific force by 58% and 24%, respectively, compared with control mice, there was no difference in tetanic [Ca(2+)](i). P(o), specific force, and tetanic [Ca(2+)](i) were reduced by 58%, 23%, and 23%, respectively, in the reloaded animals compared with control mice; however, tetanic [Ca(2+)](i) was not different between unloaded and reloaded mice. These data indicate that although hindlimb suspension results in disturbed intracellular Ca(2+) homeostasis, changes in tetanic [Ca(2+)](i) do not contribute to force deficits. Compared with unloading, 24 h of physiological reloading in the mouse do not result in further changes in maximal strength or tetanic [Ca(2+)](i).

NASA Program Biomedical Research and Countermeasur↗
DOE OSTI2020

Materials Data on Ca3(AlGe)2 by Materials Project

Ca3(AlGe)2 crystallizes in the orthorhombic Immm space group. The structure is three-dimensional. there are two inequivalent Ca sites. In the first Ca site, Ca is bonded to eight equivalent Al and four equivalent Ge atoms to form a mixture of edge and face-sharing CaAl8Ge4 cuboctahedra. All Ca–Al bond lengths are 3.33 Å. All Ca–Ge bond lengths are 3.56 Å. In the second Ca site, Ca is bonded in a 7-coordinate geometry to two equivalent Al and five equivalent Ge atoms. Both Ca–Al bond lengths are 3.17 Å. There are one shorter (3.14 Å) and four longer (3.16 Å) Ca–Ge bond lengths. Al is bonded in a 2-coordinate geometry to six Ca, one Al, and two equivalent Ge atoms. The Al–Al bond length is 2.54 Å. Both Al–Ge bond lengths are 2.53 Å. Ge is bonded in a 7-coordinate geometry to seven Ca and two equivalent Al atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ca3Al7Cu2 by Materials Project

Ca3Cu2Al7 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 in a 6-coordinate geometry to six equivalent Cu and twelve equivalent Al atoms. All Ca–Cu bond lengths are 3.22 Å. All Ca–Al bond lengths are 3.43 Å. In the second Ca site, Ca is bonded in a 12-coordinate geometry to twelve Al atoms. There are a spread of Ca–Al bond distances ranging from 3.26–3.32 Å. Cu is bonded in a 9-coordinate geometry to three equivalent Ca and six equivalent Al atoms. There are three shorter (2.54 Å) and three longer (2.59 Å) Cu–Al bond lengths. There are two inequivalent Al sites. In the first Al site, Al is bonded to six equivalent Ca and six equivalent Al atoms to form AlCa6Al6 cuboctahedra that share corners with twelve equivalent AlCa5Al5Cu2 cuboctahedra, edges with six equivalent AlCa6Al6 cuboctahedra, and faces with eighteen equivalent AlCa5Al5Cu2 cuboctahedra. All Al–Al bond lengths are 2.82 Å. In the second Al site, Al is bonded to five Ca, two equivalent Cu, and five Al atoms to form distorted AlCa5Al5Cu2 cuboctahedra that share corners with seventeen AlCa6Al6 cuboctahedra, edges with eight equivalent AlCa5Al5Cu2 cuboctahedra, and faces with fourteen AlCa6Al6 cuboctahedra. There are two shorter (2.75 Å) and two longer (2.83 Å) Al–Al bond lengths.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ca3Al7Ag2 by Materials Project

Ca3Ag2Al7 is Frank-Kasper $\mu$ Phase-derived 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 in a distorted hexagonal planar geometry to six equivalent Ag and twelve equivalent Al atoms. All Ca–Ag bond lengths are 3.26 Å. All Ca–Al bond lengths are 3.59 Å. In the second Ca site, Ca is bonded in a 12-coordinate geometry to twelve Al atoms. There are a spread of Ca–Al bond distances ranging from 3.26–3.31 Å. Ag is bonded in a 9-coordinate geometry to three equivalent Ca and six equivalent Al atoms. There are three shorter (2.72 Å) and three longer (2.78 Å) Ag–Al bond lengths. There are two inequivalent Al sites. In the first Al site, Al is bonded in a 12-coordinate geometry to five Ca, two equivalent Ag, and five Al atoms. There are a spread of Al–Al bond distances ranging from 2.77–2.87 Å. In the second Al site, Al is bonded to six equivalent Ca and six equivalent Al atoms to form edge-sharing AlCa6Al6 cuboctahedra.

36 MATERIALS SCIENCE↗