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DOE OSTI2020

Materials Data on SrRuO3 by Materials Project

SrRuO3 crystallizes in the orthorhombic Pnma space group. The structure is two-dimensional and consists of two RuO2 sheets oriented in the (0, 0, 1) direction and two SrO sheets oriented in the (0, 0, 1) direction. In each RuO2 sheet, Ru4+ is bonded in a square co-planar geometry to four equivalent O2- atoms. All Ru–O bond lengths are 1.83 Å. O2- is bonded in a linear geometry to two equivalent Ru4+ atoms. In each SrO sheet, Sr2+ is bonded in a square co-planar geometry to four equivalent O2- atoms. There are two shorter (2.59 Å) and two longer (2.60 Å) Sr–O bond lengths. O2- is bonded in a square co-planar geometry to four equivalent Sr2+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Bi4Te7Pb by Materials Project

PbBi4Te7 is MAX Phase-like structured and crystallizes in the trigonal P-3m1 space group. The structure is two-dimensional and consists of one Bi2Te3 sheet oriented in the (0, 0, 1) direction and one PbBi2Te4 sheet oriented in the (0, 0, 1) direction. In the Bi2Te3 sheet, Bi3+ is bonded to six Te2- atoms to form a mixture of corner and edge-sharing BiTe6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are three shorter (3.10 Å) and three longer (3.29 Å) Bi–Te bond lengths. There are two inequivalent Te2- sites. In the first Te2- site, Te2- is bonded in a 6-coordinate geometry to three equivalent Bi3+ atoms. In the second Te2- site, Te2- is bonded to six equivalent Bi3+ atoms to form edge-sharing TeBi6 octahedra. In the PbBi2Te4 sheet, Pb2+ is bonded to six equivalent Te2- atoms to form PbTe6 octahedra that share corners with six equivalent BiTe6 octahedra, edges with six equivalent PbTe6 octahedra, and edges with six equivalent BiTe6 octahedra. The corner-sharing octahedral tilt angles are 1°. All Pb–Te bond lengths are 3.26 Å. Bi3+ is bonded to six Te2- atoms to form BiTe6 octahedra that share corners with three equivalent PbTe6 octahedra, edges with three equivalent PbTe6 octahedra, and edges with six equivalent BiTe6 octahedra. The corner-sharing octahedral tilt angles are 1°. There are three shorter (3.09 Å) and three longer (3.30 Å) Bi–Te bond lengths. There are two inequivalent Te2- sites. In the first Te2- site, Te2- is bonded to three equivalent Pb2+ and three equivalent Bi3+ atoms to form a mixture of corner and edge-sharing TeBi3Pb3 octahedra. The corner-sharing octahedral tilt angles are 0°. In the second Te2- site, Te2- is bonded in a 6-coordinate geometry to three equivalent Bi3+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on CuBiSeO by Materials Project

BiCuSeO is Parent of FeAs superconductors structured and crystallizes in the tetragonal P4/nmm space group. The structure is two-dimensional and consists of one BiO sheet oriented in the (0, 0, 1) direction and one CuSe sheet oriented in the (0, 0, 1) direction. In the BiO sheet, Bi3+ is bonded in a 4-coordinate geometry to four equivalent O2- atoms. All Bi–O bond lengths are 2.35 Å. O2- is bonded to four equivalent Bi3+ atoms to form a mixture of edge and corner-sharing OBi4 tetrahedra. In the CuSe sheet, Cu1+ is bonded to four equivalent Se2- atoms to form a mixture of edge and corner-sharing CuSe4 tetrahedra. All Cu–Se bond lengths are 2.52 Å. Se2- is bonded in a 4-coordinate geometry to four equivalent Cu1+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on GeSb4Te7 by Materials Project

Ge1Sb4Te7 is MAX Phase-like structured and crystallizes in the trigonal P-3m1 space group. The structure is two-dimensional and consists of one Ge(SbTe2)2 sheet oriented in the (0, 0, 1) direction and one Sb2Te3 sheet oriented in the (0, 0, 1) direction. In the Ge(SbTe2)2 sheet, Ge4+ is bonded to six equivalent Te2- atoms to form GeTe6 octahedra that share corners with six equivalent SbTe6 octahedra, edges with six equivalent GeTe6 octahedra, and edges with six equivalent SbTe6 octahedra. The corner-sharing octahedral tilt angles are 5°. All Ge–Te bond lengths are 3.02 Å. Sb+2.50+ is bonded to six Te2- atoms to form SbTe6 octahedra that share corners with three equivalent GeTe6 octahedra, edges with three equivalent GeTe6 octahedra, and edges with six equivalent SbTe6 octahedra. The corner-sharing octahedral tilt angles are 5°. There are three shorter (3.02 Å) and three longer (3.21 Å) Sb–Te bond lengths. There are two inequivalent Te2- sites. In the first Te2- site, Te2- is bonded to three equivalent Ge4+ and three equivalent Sb+2.50+ atoms to form a mixture of corner and edge-sharing TeGe3Sb3 octahedra. The corner-sharing octahedral tilt angles are 0°. In the second Te2- site, Te2- is bonded in a 3-coordinate geometry to three equivalent Sb+2.50+ atoms. In the Sb2Te3 sheet, Sb+2.50+ is bonded to six Te2- atoms to form a mixture of corner and edge-sharing SbTe6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are three shorter (3.03 Å) and three longer (3.19 Å) Sb–Te bond lengths. There are two inequivalent Te2- sites. In the first Te2- site, Te2- is bonded to six equivalent Sb+2.50+ atoms to form edge-sharing TeSb6 octahedra. In the second Te2- site, Te2- is bonded in a 3-coordinate geometry to three equivalent Sb+2.50+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on GeBi4Te7 by Materials Project

GeBi4Te7 is MAX Phase-like structured and crystallizes in the trigonal P-3m1 space group. The structure is two-dimensional and consists of one Bi2Te3 sheet oriented in the (0, 0, 1) direction and one GeBi2Te4 sheet oriented in the (0, 0, 1) direction. In the Bi2Te3 sheet, Bi3+ is bonded to six Te2- atoms to form a mixture of edge and corner-sharing BiTe6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are three shorter (3.08 Å) and three longer (3.28 Å) Bi–Te bond lengths. There are two inequivalent Te2- sites. In the first Te2- site, Te2- is bonded in a 3-coordinate geometry to three equivalent Bi3+ atoms. In the second Te2- site, Te2- is bonded to six equivalent Bi3+ atoms to form edge-sharing TeBi6 octahedra. In the GeBi2Te4 sheet, Ge2+ is bonded to six equivalent Te2- atoms to form GeTe6 octahedra that share corners with six equivalent BiTe6 octahedra, edges with six equivalent GeTe6 octahedra, and edges with six equivalent BiTe6 octahedra. The corner-sharing octahedral tilt angles are 6°. All Ge–Te bond lengths are 3.05 Å. Bi3+ is bonded to six Te2- atoms to form BiTe6 octahedra that share corners with three equivalent GeTe6 octahedra, edges with three equivalent GeTe6 octahedra, and edges with six equivalent BiTe6 octahedra. The corner-sharing octahedral tilt angles are 6°. There are three shorter (3.09 Å) and three longer (3.30 Å) Bi–Te bond lengths. There are two inequivalent Te2- sites. In the first Te2- site, Te2- is bonded to three equivalent Ge2+ and three equivalent Bi3+ atoms to form a mixture of edge and corner-sharing TeGe3Bi3 octahedra. The corner-sharing octahedral tilt angles are 0°. In the second Te2- site, Te2- is bonded in a 3-coordinate geometry to three equivalent Bi3+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on U3Si2C3 by Materials Project

(UC1)2USi2C crystallizes in the orthorhombic Immm space group. The structure is two-dimensional and consists of two UC1 sheets oriented in the (0, 0, 1) direction and two USi2C sheets oriented in the (0, 0, 1) direction. In each UC1 sheet, U4+ is bonded in a 4-coordinate geometry to four equivalent C4- atoms. All U–C bond lengths are 2.23 Å. C4- is bonded to four equivalent U4+ atoms to form a mixture of edge and corner-sharing CU4 tetrahedra. In each USi2C sheet, U4+ is bonded in a square co-planar geometry to four equivalent C4- atoms. All U–C bond lengths are 2.60 Å. Si is bonded in a single-bond geometry to one C4- atom. The Si–C bond length is 1.83 Å. C4- is bonded to four equivalent U4+ and two equivalent Si atoms to form a mixture of edge and corner-sharing CU4Si2 octahedra. The corner-sharing octahedral tilt angles are 0°.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Mg3H4O5 by Materials Project

Mg(OH)2MgOMg(OH)2 crystallizes in the trigonal P-3m1 space group. The structure is two-dimensional and consists of one Mg(OH)2 sheet oriented in the (0, 0, 1) direction and one Mg(OH)2MgO sheet oriented in the (0, 0, 1) direction. In the Mg(OH)2 sheet, Mg2+ is bonded to six equivalent O2- atoms to form edge-sharing MgO6 octahedra. All Mg–O bond lengths are 2.09 Å. H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.97 Å. O2- is bonded in a distorted single-bond geometry to three equivalent Mg2+ and one H1+ atom. In the Mg(OH)2MgO sheet, Mg2+ is bonded to six O2- atoms to form a mixture of corner and edge-sharing MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are three shorter (2.09 Å) and three longer (2.18 Å) Mg–O bond lengths. H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.97 Å. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted single-bond geometry to three equivalent Mg2+ and one H1+ atom. In the second O2- site, O2- is bonded to six equivalent Mg2+ atoms to form edge-sharing OMg6 octahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Li13Sn5 by Materials Project

Li13Sn5 crystallizes in the trigonal P-3m1 space group. The structure is two-dimensional and consists of one Li5Sn2 sheet oriented in the (0, 0, 1) direction and one Li8Sn3 sheet oriented in the (0, 0, 1) direction. In the Li5Sn2 sheet, there are three inequivalent Li sites. In the first Li site, Li is bonded in a 8-coordinate geometry to eight Li and six equivalent Sn atoms. There are six shorter (2.86 Å) and two longer (2.93 Å) Li–Li bond lengths. All Li–Sn bond lengths are 3.28 Å. In the second Li site, Li is bonded in a distorted trigonal non-coplanar geometry to one Li and three equivalent Sn atoms. All Li–Sn bond lengths are 2.92 Å. In the third Li site, Li is bonded to three equivalent Li and four equivalent Sn atoms to form a mixture of distorted face, edge, and corner-sharing LiLi3Sn4 tetrahedra. There are one shorter (2.77 Å) and three longer (2.86 Å) Li–Sn bond lengths. Sn is bonded in a 7-coordinate geometry to ten Li atoms. In the Li8Sn3 sheet, there are four inequivalent Li sites. In the first Li site, Li is bonded to three equivalent Li and four Sn atoms to form distorted LiLi3Sn4 tetrahedra that share corners with four LiLi3Sn4 tetrahedra, edges with nine LiLi3Sn4 tetrahedra, and faces with three equivalent LiLi4Sn4 tetrahedra. All Li–Li bond lengths are 2.85 Å. There are one shorter (2.79 Å) and three longer (2.89 Å) Li–Sn bond lengths. In the second Li site, Li is bonded to four equivalent Li and four Sn atoms to form a mixture of distorted face, edge, and corner-sharing LiLi4Sn4 tetrahedra. There are one shorter (2.83 Å) and three longer (2.89 Å) Li–Li bond lengths. There are three shorter (2.86 Å) and one longer (2.88 Å) Li–Sn bond lengths. In the third Li site, Li is bonded in a distorted trigonal non-coplanar geometry to one Li and three equivalent Sn atoms. The Li–Li bond length is 2.93 Å. All Li–Sn bond lengths are 2.91 Å. In the fourth Li site, Li is bonded in a 11-coordinate geometry to eight Li and six Sn atoms. There are three shorter (3.29 Å) and three longer (3.32 Å) Li–Sn bond lengths. There are two inequivalent Sn sites. In the first Sn site, Sn is bonded in a body-centered cubic geometry to fourteen Li atoms. In the second Sn site, Sn is bonded in a 7-coordinate geometry to ten Li atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on EuCuSeO by Materials Project

EuCuOSe is Parent of FeAs superconductors structured and crystallizes in the tetragonal P4/nmm space group. The structure is two-dimensional and consists of one CuSe sheet oriented in the (0, 0, 1) direction and one EuO sheet oriented in the (0, 0, 1) direction. In the CuSe sheet, Cu1+ is bonded to four equivalent Se2- atoms to form a mixture of corner and edge-sharing CuSe4 tetrahedra. All Cu–Se bond lengths are 2.49 Å. Se2- is bonded in a 4-coordinate geometry to four equivalent Cu1+ atoms. In the EuO sheet, Eu3+ is bonded in a 4-coordinate geometry to four equivalent O2- atoms. All Eu–O bond lengths are 2.30 Å. O2- is bonded to four equivalent Eu3+ atoms to form a mixture of corner and edge-sharing OEu4 tetrahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Te3Pt2 by Materials Project

Pt2Te3 crystallizes in the trigonal R-3m space group. The structure is two-dimensional and consists of six PtTe sheets oriented in the (0, 0, 1) direction and six PtTe2 sheets oriented in the (0, 0, 1) direction. In each PtTe sheet, Pt3+ is bonded in a distorted trigonal non-coplanar geometry to three equivalent Te2- atoms. All Pt–Te bond lengths are 2.64 Å. Te2- is bonded in a distorted trigonal non-coplanar geometry to three equivalent Pt3+ atoms. In each PtTe2 sheet, Pt3+ is bonded to six Te2- atoms to form edge-sharing PtTe6 octahedra. There are three shorter (2.71 Å) and three longer (2.72 Å) Pt–Te bond lengths. There are two inequivalent Te2- sites. In the first Te2- site, Te2- is bonded in a 3-coordinate geometry to three equivalent Pt3+ atoms. In the second Te2- site, Te2- is bonded in a 3-coordinate geometry to three equivalent Pt3+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on NdCuSO by Materials Project

(NdO)CuS is Parent of FeAs superconductors structured and crystallizes in the tetragonal P4/nmm space group. The structure is two-dimensional and consists of one CuS sheet oriented in the (0, 0, 1) direction and one NdO sheet oriented in the (0, 0, 1) direction. In the CuS sheet, Cu1+ is bonded to four equivalent S2- atoms to form a mixture of edge and corner-sharing CuS4 tetrahedra. All Cu–S bond lengths are 2.42 Å. S2- is bonded in a 4-coordinate geometry to four equivalent Cu1+ atoms. In the NdO sheet, Nd3+ is bonded in a 4-coordinate geometry to four equivalent O2- atoms. All Nd–O bond lengths are 2.32 Å. O2- is bonded to four equivalent Nd3+ atoms to form a mixture of edge and corner-sharing ONd4 tetrahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Hg(SbS2)4 by Materials Project

Hg(SbS2)2(SbS2)2 is Stibnite-derived structured and crystallizes in the monoclinic C2/c space group. The structure is two-dimensional and consists of two Hg(SbS2)2 sheets oriented in the (1, 0, 0) direction and two SbS2 sheets oriented in the (1, 0, 0) direction. In each Hg(SbS2)2 sheet, there are two inequivalent Hg2+ sites. In the first Hg2+ site, Hg2+ is bonded in a distorted linear geometry to six S2- atoms. There are a spread of Hg–S bond distances ranging from 2.38–3.44 Å. In the second Hg2+ site, Hg2+ is bonded in a distorted linear geometry to six S2- atoms. There are a spread of Hg–S bond distances ranging from 2.38–3.45 Å. There are two inequivalent Sb+3.50+ sites. In the first Sb+3.50+ site, Sb+3.50+ is bonded to five S2- atoms to form edge-sharing SbS5 square pyramids. There are a spread of Sb–S bond distances ranging from 2.49–2.94 Å. In the second Sb+3.50+ site, Sb+3.50+ is bonded to five S2- atoms to form edge-sharing SbS5 square pyramids. There are a spread of Sb–S bond distances ranging from 2.49–2.94 Å. There are four inequivalent S2- sites. In the first S2- site, S2- is bonded in a 5-coordinate geometry to two equivalent Hg2+ and three Sb+3.50+ atoms. In the second S2- site, S2- is bonded in a distorted trigonal non-coplanar geometry to one Hg2+ and two equivalent Sb+3.50+ atoms. In the third S2- site, S2- is bonded in a 5-coordinate geometry to two equivalent Hg2+ and three Sb+3.50+ atoms. In the fourth S2- site, S2- is bonded in a distorted trigonal non-coplanar geometry to one Hg2+ and two equivalent Sb+3.50+ atoms. In each SbS2 sheet, there are two inequivalent Sb+3.50+ sites. In the first Sb+3.50+ site, Sb+3.50+ is bonded to five S2- atoms to form distorted edge-sharing SbS5 square pyramids. There are a spread of Sb–S bond distances ranging from 2.50–3.00 Å. In the second Sb+3.50+ site, Sb+3.50+ is bonded to five S2- atoms to form distorted edge-sharing SbS5 square pyramids. There are a spread of Sb–S bond distances ranging from 2.50–3.02 Å. There are four inequivalent S2- sites. In the first S2- site, S2- is bonded in a 3-coordinate geometry to two equivalent Sb+3.50+ and one S2- atom. The S–S bond length is 2.08 Å. In the second S2- site, S2- is bonded in a 3-coordinate geometry to three equivalent Sb+3.50+ atoms. In the third S2- site, S2- is bonded in a 3-coordinate geometry to two equivalent Sb+3.50+ and one S2- atom. In the fourth S2- site, S2- is bonded in a 3-coordinate geometry to three equivalent Sb+3.50+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on CuBiTeO by Materials Project

BiCuOTe is Parent of FeAs superconductors structured and crystallizes in the tetragonal P4/nmm space group. The structure is two-dimensional and consists of one BiO sheet oriented in the (0, 0, 1) direction and one CuTe sheet oriented in the (0, 0, 1) direction. In the BiO sheet, Bi3+ is bonded in a 4-coordinate geometry to four equivalent O2- atoms. All Bi–O bond lengths are 2.37 Å. O2- is bonded to four equivalent Bi3+ atoms to form a mixture of edge and corner-sharing OBi4 tetrahedra. In the CuTe sheet, Cu1+ is bonded to four equivalent Te2- atoms to form a mixture of edge and corner-sharing CuTe4 tetrahedra. All Cu–Te bond lengths are 2.67 Å. Te2- is bonded in a 12-coordinate geometry to four equivalent Cu1+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on BaBi4(IO2)2 by Materials Project

BaOBi2O3(BiI)2 crystallizes in the tetragonal I4/mmm space group. The structure is two-dimensional and consists of two BaOBi2O3 sheets oriented in the (0, 0, 1) direction and four BiI sheets oriented in the (0, 0, 1) direction. In each BaOBi2O3 sheet, Ba2+ is bonded in a body-centered cubic geometry to eight equivalent O2- atoms. All Ba–O bond lengths are 2.76 Å. Bi2+ is bonded to four equivalent O2- atoms to form distorted corner-sharing BiO4 trigonal pyramids. All Bi–O bond lengths are 2.24 Å. O2- is bonded to two equivalent Ba2+ and two equivalent Bi2+ atoms to form a mixture of distorted corner and edge-sharing OBa2Bi2 tetrahedra. In each BiI sheet, Bi2+ is bonded in a 4-coordinate geometry to four equivalent I1- atoms. All Bi–I bond lengths are 3.51 Å. I1- is bonded in a 4-coordinate geometry to four equivalent Bi2+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on YCu2Bi2(SeO2)2 by Materials Project

Bi2YO4Cu2Se2 crystallizes in the tetragonal I4/mmm space group. The structure is two-dimensional and consists of two CuSe sheets oriented in the (0, 0, 1) direction and two Y(BiO2)2 sheets oriented in the (0, 0, 1) direction. In each CuSe sheet, Cu+1.50+ is bonded to four equivalent Se2- atoms to form a mixture of edge and corner-sharing CuSe4 tetrahedra. All Cu–Se bond lengths are 2.47 Å. Se2- is bonded in a 4-coordinate geometry to four equivalent Cu+1.50+ atoms. In each Y(BiO2)2 sheet, Y3+ is bonded in a body-centered cubic geometry to eight equivalent O2- atoms. All Y–O bond lengths are 2.40 Å. Bi3+ is bonded in a 4-coordinate geometry to four equivalent O2- atoms. All Bi–O bond lengths are 2.25 Å. O2- is bonded to two equivalent Y3+ and two equivalent Bi3+ atoms to form a mixture of edge and corner-sharing OY2Bi2 tetrahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on LaCuSeO by Materials Project

LaCuOSe is Parent of FeAs superconductors structured and crystallizes in the tetragonal P4/nmm space group. The structure is two-dimensional and consists of one CuSe sheet oriented in the (0, 0, 1) direction and one LaO sheet oriented in the (0, 0, 1) direction. In the CuSe sheet, Cu1+ is bonded to four equivalent Se2- atoms to form a mixture of corner and edge-sharing CuSe4 tetrahedra. All Cu–Se bond lengths are 2.52 Å. Se2- is bonded in a 4-coordinate geometry to four equivalent Cu1+ atoms. In the LaO sheet, La3+ is bonded in a 4-coordinate geometry to four equivalent O2- atoms. All La–O bond lengths are 2.38 Å. O2- is bonded to four equivalent La3+ atoms to form a mixture of corner and edge-sharing OLa4 tetrahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on RbBr3 by Materials Project

RbBr(Br)2 crystallizes in the tetragonal I4/mmm space group. The structure is two-dimensional and consists of two Br sheets oriented in the (0, 0, 1) direction and two RbBr sheets oriented in the (0, 0, 1) direction. In each Br sheet, Br is bonded in a distorted square co-planar geometry to four equivalent Br atoms. All Br–Br bond lengths are 3.17 Å. In each RbBr sheet, Rb is bonded in a square co-planar geometry to four equivalent Br atoms. All Rb–Br bond lengths are 3.17 Å. Br is bonded in a square co-planar geometry to four equivalent Rb atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on CaNb2Bi2O9 by Materials Project

CaBi2Nb2O9 crystallizes in the monoclinic C2/m space group. The structure is two-dimensional and consists of one BiO2 sheet oriented in the (0, 0, 1) direction and one CaNb2O5 sheet oriented in the (0, 0, 1) direction. In the BiO2 sheet, Bi3+ is bonded in a 4-coordinate geometry to eight O2- atoms. There are a spread of Bi–O bond distances ranging from 2.33–2.92 Å. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to four equivalent Bi3+ atoms. In the second O2- site, O2- is bonded to four equivalent Bi3+ atoms to form a mixture of edge and corner-sharing OBi4 tetrahedra. In the CaNb2O5 sheet, Ca2+ is bonded to twelve O2- atoms to form CaO12 cuboctahedra that share corners with four equivalent CaO12 cuboctahedra, faces with four equivalent CaO12 cuboctahedra, and faces with eight equivalent NbO5 square pyramids. There are eight shorter (2.73 Å) and four longer (2.77 Å) Ca–O bond lengths. Nb5+ is bonded to five O2- atoms to form NbO5 square pyramids that share corners with five equivalent NbO5 square pyramids and faces with four equivalent CaO12 cuboctahedra. There is four shorter (1.96 Å) and one longer (1.97 Å) Nb–O bond length. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted linear geometry to four equivalent Ca2+ and two equivalent Nb5+ atoms. In the second O2- site, O2- is bonded in a distorted linear geometry to two equivalent Ca2+ and two equivalent Nb5+ atoms.

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