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DOE OSTI2020

Materials Data on ZnCr2O4 by Materials Project

ZnCr2O4 crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are four inequivalent Cr3+ sites. In the first Cr3+ site, Cr3+ is bonded to six O2- atoms to form CrO6 octahedra that share corners with four CrO6 octahedra, corners with two equivalent ZnO5 square pyramids, edges with four CrO6 octahedra, and edges with three ZnO5 square pyramids. The corner-sharing octahedra tilt angles range from 49–56°. There are a spread of Cr–O bond distances ranging from 1.95–2.18 Å. In the second Cr3+ site, Cr3+ is bonded to six O2- atoms to form CrO6 octahedra that share corners with four CrO6 octahedra, corners with four ZnO5 square pyramids, edges with four CrO6 octahedra, and a faceface with one ZnO5 square pyramid. The corner-sharing octahedra tilt angles range from 49–56°. There are a spread of Cr–O bond distances ranging from 1.94–2.20 Å. In the third Cr3+ site, Cr3+ is bonded to six O2- atoms to form CrO6 octahedra that share corners with four CrO6 octahedra, corners with four ZnO5 square pyramids, edges with four CrO6 octahedra, and a faceface with one ZnO5 square pyramid. The corner-sharing octahedra tilt angles range from 49–56°. There are a spread of Cr–O bond distances ranging from 1.94–2.19 Å. In the fourth Cr3+ site, Cr3+ is bonded to six O2- atoms to form CrO6 octahedra that share corners with four CrO6 octahedra, corners with two equivalent ZnO5 square pyramids, edges with four CrO6 octahedra, and edges with three ZnO5 square pyramids. The corner-sharing octahedra tilt angles range from 49–56°. There are a spread of Cr–O bond distances ranging from 1.95–2.18 Å. There are two inequivalent Zn2+ sites. In the first Zn2+ site, Zn2+ is bonded to five O2- atoms to form ZnO5 square pyramids that share corners with six CrO6 octahedra, edges with three CrO6 octahedra, edges with two equivalent ZnO5 square pyramids, and a faceface with one CrO6 octahedra. The corner-sharing octahedra tilt angles range from 10–58°. There are a spread of Zn–O bond distances ranging from 2.09–2.15 Å. In the second Zn2+ site, Zn2+ is bonded to five O2- atoms to form ZnO5 square pyramids that share corners with six CrO6 octahedra, edges with three CrO6 octahedra, edges with two equivalent ZnO5 square pyramids, and a faceface with one CrO6 octahedra. The corner-sharing octahedra tilt angles range from 10–58°. There are a spread of Zn–O bond distances ranging from 2.09–2.14 Å. There are eight inequivalent O2- sites. In the first O2- site, O2- is bonded to three Cr3+ and one Zn2+ atom to form OZnCr3 trigonal pyramids that share corners with two equivalent OZn2Cr3 square pyramids, corners with two equivalent OZnCr3 trigonal pyramids, edges with three OZn2Cr3 square pyramids, and edges with two equivalent OZn2Cr3 trigonal bipyramids. In the second O2- site, O2- is bonded in a trigonal planar geometry to three Cr3+ atoms. In the third O2- site, O2- is bonded in a trigonal planar geometry to three Cr3+ atoms. In the fourth O2- site, O2- is bonded to three Cr3+ and one Zn2+ atom to form OZnCr3 trigonal pyramids that share corners with two equivalent OZn2Cr3 square pyramids, a cornercorner with one OZn2Cr3 trigonal bipyramid, corners with two equivalent OZnCr3 trigonal pyramids, and edges with three OZn2Cr3 square pyramids. In the fifth O2- site, O2- is bonded to three Cr3+ and two equivalent Zn2+ atoms to form OZn2Cr3 square pyramids that share corners with two equivalent OZn2Cr3 trigonal bipyramids, corners with two equivalent OZnCr3 trigonal pyramids, edges with four OZn2Cr3 square pyramids, an edgeedge with one OZn2Cr3 trigonal bipyramid, and edges with three OZnCr3 trigonal pyramids. In the sixth O2- site, O2- is bonded in a 5-coordinate geometry to three Cr3+ and two equivalent Zn2+ atoms. In the seventh O2- site, O2- is bonded to three Cr3+ and two equivalent Zn2+ atoms to form OZn2Cr3 square pyramids that share corners with two equivalent OZnCr3 trigonal pyramids, edges with four OZn2Cr3 square pyramids, and edges with three OZnCr3 trigonal pyramids. In the eighth O2- site, O2- is bonded to three Cr3+ and two equivalent Zn2+ atoms to form distorted OZn2Cr3 trigonal bipyramids that share corners with two equivalent OZn2Cr3 square pyramids, a cornercorner with one OZnCr3 trigonal pyramid, an edgeedge with one OZn2Cr3 square pyramid, edges with two equivalent OZn2Cr3 trigonal bipyramids, and edges with two equivalent OZnCr3 trigonal pyramids.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on ZnCrO2 by Materials Project

ZnCrO2 crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are four inequivalent Cr2+ sites. In the first Cr2+ site, Cr2+ is bonded to five O2- atoms to form CrO5 square pyramids that share corners with two equivalent CrO6 octahedra, corners with three ZnO4 tetrahedra, edges with two equivalent CrO6 octahedra, and edges with two equivalent CrO5 square pyramids. The corner-sharing octahedra tilt angles range from 48–51°. There are a spread of Cr–O bond distances ranging from 1.99–2.13 Å. In the second Cr2+ site, Cr2+ is bonded to six O2- atoms to form CrO6 octahedra that share corners with two equivalent CrO6 octahedra, corners with two equivalent CrO5 square pyramids, corners with four ZnO4 tetrahedra, and edges with two equivalent CrO6 octahedra. The corner-sharing octahedra tilt angles range from 49–52°. There are a spread of Cr–O bond distances ranging from 2.00–2.11 Å. In the third Cr2+ site, Cr2+ is bonded in a distorted T-shaped geometry to three O2- atoms. There are a spread of Cr–O bond distances ranging from 2.01–2.08 Å. In the fourth Cr2+ site, Cr2+ is bonded to six O2- atoms to form CrO6 octahedra that share corners with two equivalent CrO6 octahedra, corners with three ZnO4 tetrahedra, edges with two equivalent CrO6 octahedra, and edges with two equivalent CrO5 square pyramids. The corner-sharing octahedra tilt angles range from 49–52°. There are a spread of Cr–O bond distances ranging from 2.02–2.17 Å. There are four inequivalent Zn2+ sites. In the first Zn2+ site, Zn2+ is bonded to four O2- atoms to form distorted ZnO4 tetrahedra that share corners with four CrO6 octahedra, a cornercorner with one CrO5 square pyramid, and corners with four ZnO4 tetrahedra. The corner-sharing octahedra tilt angles range from 49–68°. There are a spread of Zn–O bond distances ranging from 1.97–2.06 Å. In the second Zn2+ site, Zn2+ is bonded to four O2- atoms to form distorted ZnO4 tetrahedra that share corners with three CrO6 octahedra, corners with two equivalent CrO5 square pyramids, and corners with four ZnO4 tetrahedra. The corner-sharing octahedra tilt angles range from 56–64°. There are a spread of Zn–O bond distances ranging from 1.96–2.18 Å. In the third Zn2+ site, Zn2+ is bonded in a 2-coordinate geometry to two O2- atoms. There are one shorter (1.97 Å) and one longer (2.34 Å) Zn–O bond lengths. In the fourth Zn2+ site, Zn2+ is bonded in a 2-coordinate geometry to three O2- atoms. There are a spread of Zn–O bond distances ranging from 2.00–2.60 Å. There are eight inequivalent O2- sites. In the first O2- site, O2- is bonded in a 5-coordinate geometry to three Cr2+ and two equivalent Zn2+ atoms. In the second O2- site, O2- is bonded in a 4-coordinate geometry to four Zn2+ atoms. In the third O2- site, O2- is bonded to three Cr2+ and one Zn2+ atom to form distorted OZnCr3 trigonal pyramids that share a cornercorner with one OZn2Cr3 square pyramid, corners with two equivalent OZnCr3 tetrahedra, corners with six OZnCr3 trigonal pyramids, and an edgeedge with one OZnCr3 tetrahedra. In the fourth O2- site, O2- is bonded in a 3-coordinate geometry to three Cr2+ atoms. In the fifth O2- site, O2- is bonded to three Cr2+ and two Zn2+ atoms to form distorted OZn2Cr3 square pyramids that share corners with two equivalent OZn2Cr3 square pyramids, corners with three OZnCr3 trigonal pyramids, and edges with two equivalent OZnCr3 trigonal pyramids. In the sixth O2- site, O2- is bonded to three Cr2+ and one Zn2+ atom to form a mixture of corner and edge-sharing OZnCr3 tetrahedra. In the seventh O2- site, O2- is bonded to three Cr2+ and one Zn2+ atom to form OZnCr3 trigonal pyramids that share a cornercorner with one OZnCr3 tetrahedra, corners with four OZnCr3 trigonal pyramids, and edges with two equivalent OZn2Cr3 square pyramids. In the eighth O2- site, O2- is bonded to two Cr2+ and two equivalent Zn2+ atoms to form distorted OZn2Cr2 trigonal pyramids that share corners with two equivalent OZn2Cr3 square pyramids, a cornercorner with one OZnCr3 tetrahedra, corners with four OZnCr3 trigonal pyramids, and an edgeedge with one OZnCr3 tetrahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on ZnCr2O4 by Materials Project

ZnCr2O4 crystallizes in the orthorhombic Pmmn space group. The structure is three-dimensional. there are two inequivalent Cr3+ sites. In the first Cr3+ site, Cr3+ is bonded to six O2- atoms to form CrO6 octahedra that share corners with three equivalent ZnO6 pentagonal pyramids, edges with six CrO6 octahedra, and an edgeedge with one ZnO6 pentagonal pyramid. There are a spread of Cr–O bond distances ranging from 1.99–2.09 Å. In the second Cr3+ site, Cr3+ is bonded to six O2- atoms to form CrO6 octahedra that share edges with six CrO6 octahedra and edges with two equivalent ZnO6 pentagonal pyramids. There are two shorter (1.98 Å) and four longer (2.04 Å) Cr–O bond lengths. There are two inequivalent Zn2+ sites. In the first Zn2+ site, Zn2+ is bonded to six O2- atoms to form distorted ZnO6 pentagonal pyramids that share corners with six equivalent CrO6 octahedra and edges with six CrO6 octahedra. The corner-sharing octahedra tilt angles range from 5–18°. There are two shorter (2.05 Å) and four longer (2.32 Å) Zn–O bond lengths. In the second Zn2+ site, Zn2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are two shorter (2.08 Å) and four longer (2.32 Å) Zn–O bond lengths. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a rectangular see-saw-like geometry to three Cr3+ and one Zn2+ atom. In the second O2- site, O2- is bonded to three Cr3+ and one Zn2+ atom to form OZnCr3 trigonal pyramids that share corners with four equivalent OZn2Cr3 trigonal bipyramids, corners with three equivalent OZnCr3 trigonal pyramids, and edges with four equivalent OZn2Cr3 trigonal bipyramids. In the third O2- site, O2- is bonded to three Cr3+ and two Zn2+ atoms to form distorted OZn2Cr3 trigonal bipyramids that share corners with five equivalent OZn2Cr3 trigonal bipyramids, corners with two equivalent OZnCr3 trigonal pyramids, edges with four equivalent OZn2Cr3 trigonal bipyramids, and edges with two equivalent OZnCr3 trigonal pyramids.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on ZnCrO2 by Materials Project

ZnCrO2 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are two inequivalent Cr2+ sites. In the first Cr2+ site, Cr2+ is bonded in a square co-planar geometry to four O2- atoms. There are two shorter (1.98 Å) and two longer (2.17 Å) Cr–O bond lengths. In the second Cr2+ site, Cr2+ is bonded to five O2- atoms to form distorted CrO5 trigonal bipyramids that share corners with four equivalent ZnO4 tetrahedra, corners with two equivalent ZnO5 trigonal bipyramids, an edgeedge with one ZnO4 tetrahedra, edges with two equivalent CrO5 trigonal bipyramids, and a faceface with one ZnO5 trigonal bipyramid. There are a spread of Cr–O bond distances ranging from 2.07–2.26 Å. There are two inequivalent Zn2+ sites. In the first Zn2+ site, Zn2+ is bonded to five O2- atoms to form ZnO5 trigonal bipyramids that share corners with four equivalent ZnO4 tetrahedra, corners with two equivalent CrO5 trigonal bipyramids, edges with two equivalent ZnO5 trigonal bipyramids, and a faceface with one CrO5 trigonal bipyramid. There are a spread of Zn–O bond distances ranging from 2.01–2.17 Å. In the second Zn2+ site, Zn2+ is bonded to four O2- atoms to form ZnO4 tetrahedra that share corners with two equivalent ZnO4 tetrahedra, corners with four equivalent CrO5 trigonal bipyramids, corners with four equivalent ZnO5 trigonal bipyramids, and an edgeedge with one CrO5 trigonal bipyramid. There are a spread of Zn–O bond distances ranging from 1.97–2.03 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded to three Cr2+ and one Zn2+ atom to form distorted OZnCr3 tetrahedra that share corners with two equivalent OZnCr3 tetrahedra, corners with four equivalent OZn3Cr2 trigonal bipyramids, and edges with three OZn3Cr2 trigonal bipyramids. In the second O2- site, O2- is bonded in a rectangular see-saw-like geometry to two equivalent Cr2+ and two equivalent Zn2+ atoms. In the third O2- site, O2- is bonded to two equivalent Cr2+ and three Zn2+ atoms to form distorted OZn3Cr2 trigonal bipyramids that share corners with four equivalent OZnCr3 tetrahedra, corners with three equivalent OZn3Cr2 trigonal bipyramids, an edgeedge with one OZnCr3 tetrahedra, and edges with three OZn3Cr2 trigonal bipyramids. In the fourth O2- site, O2- is bonded to two equivalent Cr2+ and three Zn2+ atoms to form distorted OZn3Cr2 trigonal bipyramids that share corners with three equivalent OZn3Cr2 trigonal bipyramids, edges with two equivalent OZnCr3 tetrahedra, and edges with three OZn3Cr2 trigonal bipyramids.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Zn2Cr3O8 by Materials Project

Cr3Zn2O8 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. there are two inequivalent Cr4+ sites. In the first Cr4+ site, Cr4+ is bonded to six O2- atoms to form edge-sharing CrO6 octahedra. There is four shorter (1.93 Å) and two longer (1.99 Å) Cr–O bond length. In the second Cr4+ site, Cr4+ is bonded to six O2- atoms to form edge-sharing CrO6 octahedra. There are a spread of Cr–O bond distances ranging from 1.89–2.01 Å. Zn2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Zn–O bond distances ranging from 2.07–2.33 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted trigonal planar geometry to two equivalent Cr4+ and one Zn2+ atom. In the second O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to three Cr4+ and one Zn2+ atom. In the third O2- site, O2- is bonded in a 4-coordinate geometry to two Cr4+ and two equivalent Zn2+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on ZnCr4O8 by Materials Project

Cr4ZnO8 crystallizes in the monoclinic Cm space group. The structure is three-dimensional. there are four inequivalent Cr+3.50+ sites. In the first Cr+3.50+ site, Cr+3.50+ is bonded to six O2- atoms to form CrO6 octahedra that share corners with four CrO6 octahedra, edges with four CrO6 octahedra, and edges with two equivalent ZnO5 square pyramids. The corner-sharing octahedra tilt angles range from 48–52°. There are a spread of Cr–O bond distances ranging from 1.92–2.15 Å. In the second Cr+3.50+ site, Cr+3.50+ is bonded to six O2- atoms to form distorted CrO6 octahedra that share corners with four CrO6 octahedra, corners with two equivalent ZnO5 square pyramids, edges with four CrO6 octahedra, and a faceface with one ZnO5 square pyramid. The corner-sharing octahedra tilt angles range from 48–55°. There are a spread of Cr–O bond distances ranging from 1.89–2.19 Å. In the third Cr+3.50+ site, Cr+3.50+ is bonded to six O2- atoms to form CrO6 octahedra that share corners with four CrO6 octahedra, corners with two equivalent ZnO5 square pyramids, and edges with four CrO6 octahedra. The corner-sharing octahedral tilt angles are 52°. There are a spread of Cr–O bond distances ranging from 1.92–2.06 Å. In the fourth Cr+3.50+ site, Cr+3.50+ is bonded to six O2- atoms to form CrO6 octahedra that share corners with four CrO6 octahedra, corners with two equivalent ZnO5 square pyramids, edges with four CrO6 octahedra, and an edgeedge with one ZnO5 square pyramid. The corner-sharing octahedra tilt angles range from 52–55°. There are a spread of Cr–O bond distances ranging from 1.92–2.12 Å. Zn2+ is bonded to five O2- atoms to form ZnO5 square pyramids that share corners with six CrO6 octahedra, edges with three CrO6 octahedra, edges with two equivalent ZnO5 square pyramids, and a faceface with one CrO6 octahedra. The corner-sharing octahedra tilt angles range from 6–56°. There are a spread of Zn–O bond distances ranging from 2.09–2.16 Å. There are eight inequivalent O2- sites. In the first O2- site, O2- is bonded in a trigonal planar geometry to three Cr+3.50+ atoms. In the second O2- site, O2- is bonded in a distorted trigonal planar geometry to three Cr+3.50+ atoms. In the third O2- site, O2- is bonded in a trigonal planar geometry to three Cr+3.50+ atoms. In the fourth O2- site, O2- is bonded to three Cr+3.50+ and one Zn2+ atom to form OZnCr3 trigonal pyramids that share corners with two equivalent OZnCr3 trigonal pyramids, edges with two equivalent OZn2Cr3 square pyramids, and edges with two equivalent OZn2Cr3 trigonal bipyramids. In the fifth O2- site, O2- is bonded in a trigonal non-coplanar geometry to three Cr+3.50+ atoms. In the sixth O2- site, O2- is bonded to three Cr+3.50+ and two equivalent Zn2+ atoms to form distorted OZn2Cr3 trigonal bipyramids that share corners with two equivalent OZn2Cr3 square pyramids, an edgeedge with one OZn2Cr3 square pyramid, edges with two equivalent OZn2Cr3 trigonal bipyramids, and edges with two equivalent OZnCr3 trigonal pyramids. In the seventh O2- site, O2- is bonded to three Cr+3.50+ and two equivalent Zn2+ atoms to form OZn2Cr3 square pyramids that share corners with two equivalent OZn2Cr3 trigonal bipyramids, edges with two equivalent OZn2Cr3 square pyramids, an edgeedge with one OZn2Cr3 trigonal bipyramid, and edges with two equivalent OZnCr3 trigonal pyramids. In the eighth O2- site, O2- is bonded in a trigonal non-coplanar geometry to three Cr+3.50+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on ZnCrO2 by Materials Project

ZnCrO2 crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are four inequivalent Cr2+ sites. In the first Cr2+ site, Cr2+ is bonded to five O2- atoms to form CrO5 square pyramids that share corners with four CrO5 square pyramids, corners with four ZnO5 trigonal bipyramids, edges with two equivalent CrO5 square pyramids, and an edgeedge with one ZnO5 trigonal bipyramid. There are a spread of Cr–O bond distances ranging from 1.99–2.19 Å. In the second Cr2+ site, Cr2+ is bonded to five O2- atoms to form CrO5 square pyramids that share corners with four CrO5 square pyramids, corners with two equivalent ZnO5 trigonal bipyramids, edges with two equivalent CrO5 square pyramids, and a faceface with one ZnO5 trigonal bipyramid. There are a spread of Cr–O bond distances ranging from 1.92–2.16 Å. In the third Cr2+ site, Cr2+ is bonded to five O2- atoms to form distorted CrO5 square pyramids that share corners with four CrO5 square pyramids, corners with two equivalent ZnO5 trigonal bipyramids, edges with two equivalent CrO5 square pyramids, and a faceface with one ZnO5 trigonal bipyramid. There are a spread of Cr–O bond distances ranging from 1.92–2.15 Å. In the fourth Cr2+ site, Cr2+ is bonded to five O2- atoms to form CrO5 square pyramids that share corners with four CrO5 square pyramids, corners with four ZnO5 trigonal bipyramids, edges with two equivalent CrO5 square pyramids, and an edgeedge with one ZnO5 trigonal bipyramid. There are a spread of Cr–O bond distances ranging from 1.99–2.19 Å. There are four inequivalent Zn2+ sites. In the first Zn2+ site, Zn2+ is bonded to five O2- atoms to form ZnO5 trigonal bipyramids that share corners with six CrO5 square pyramids, an edgeedge with one CrO5 square pyramid, edges with two equivalent ZnO5 trigonal bipyramids, and a faceface with one CrO5 square pyramid. There are a spread of Zn–O bond distances ranging from 2.07–2.23 Å. In the second Zn2+ site, Zn2+ is bonded to five O2- atoms to form ZnO5 trigonal bipyramids that share corners with six CrO5 square pyramids, an edgeedge with one CrO5 square pyramid, edges with two equivalent ZnO5 trigonal bipyramids, and a faceface with one CrO5 square pyramid. There are a spread of Zn–O bond distances ranging from 2.07–2.24 Å. In the third Zn2+ site, Zn2+ is bonded in a water-like geometry to two O2- atoms. There are one shorter (2.06 Å) and one longer (2.08 Å) Zn–O bond lengths. In the fourth Zn2+ site, Zn2+ is bonded in a water-like geometry to two O2- atoms. There are one shorter (2.07 Å) and one longer (2.08 Å) Zn–O bond lengths. There are eight inequivalent O2- sites. In the first O2- site, O2- is bonded to three Cr2+ and one Zn2+ atom to form distorted OZnCr3 tetrahedra that share corners with two equivalent OZnCr3 tetrahedra and edges with two equivalent OZn3Cr2 trigonal bipyramids. In the second O2- site, O2- is bonded in a distorted trigonal planar geometry to three Cr2+ atoms. In the third O2- site, O2- is bonded in a distorted trigonal planar geometry to three Cr2+ atoms. In the fourth O2- site, O2- is bonded to three Cr2+ and one Zn2+ atom to form distorted OZnCr3 tetrahedra that share corners with two equivalent OZnCr3 tetrahedra and edges with two equivalent OZn3Cr2 trigonal bipyramids. In the fifth O2- site, O2- is bonded in a 5-coordinate geometry to two equivalent Cr2+ and three Zn2+ atoms. In the sixth O2- site, O2- is bonded to two equivalent Cr2+ and three Zn2+ atoms to form distorted OZn3Cr2 trigonal bipyramids that share edges with two equivalent OZnCr3 tetrahedra and edges with two equivalent OZn3Cr2 trigonal bipyramids. In the seventh O2- site, O2- is bonded in a 5-coordinate geometry to two equivalent Cr2+ and three Zn2+ atoms. In the eighth O2- site, O2- is bonded to two equivalent Cr2+ and three Zn2+ atoms to form distorted OZn3Cr2 trigonal bipyramids that share edges with two equivalent OZnCr3 tetrahedra and edges with two equivalent OZn3Cr2 trigonal bipyramids.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on ZnCr2O4 by Materials Project

ZnCr2O4 is Spinel-like structured and crystallizes in the monoclinic Cm space group. The structure is three-dimensional. there are nine inequivalent Cr3+ sites. In the first Cr3+ site, Cr3+ is bonded to six O2- atoms to form CrO6 octahedra that share corners with two equivalent ZnO4 tetrahedra, corners with four CrO4 tetrahedra, edges with three CrO6 octahedra, and edges with three ZnO6 octahedra. There are a spread of Cr–O bond distances ranging from 1.99–2.04 Å. In the second Cr3+ site, Cr3+ is bonded to four O2- atoms to form CrO4 tetrahedra that share corners with six CrO6 octahedra and corners with six ZnO6 octahedra. The corner-sharing octahedra tilt angles range from 51–68°. There are a spread of Cr–O bond distances ranging from 1.91–2.00 Å. In the third Cr3+ site, Cr3+ is bonded to six O2- atoms to form CrO6 octahedra that share corners with three equivalent CrO4 tetrahedra, corners with three equivalent ZnO4 tetrahedra, edges with two ZnO6 octahedra, and edges with four CrO6 octahedra. There are a spread of Cr–O bond distances ranging from 1.99–2.06 Å. In the fourth Cr3+ site, Cr3+ is bonded to six O2- atoms to form CrO6 octahedra that share corners with six CrO4 tetrahedra, edges with two equivalent CrO6 octahedra, and edges with four ZnO6 octahedra. There are one shorter (2.03 Å) and five longer (2.04 Å) Cr–O bond lengths. In the fifth Cr3+ site, Cr3+ is bonded to four O2- atoms to form CrO4 tetrahedra that share corners with six CrO6 octahedra and corners with six ZnO6 octahedra. The corner-sharing octahedra tilt angles range from 52–69°. There are a spread of Cr–O bond distances ranging from 1.90–2.00 Å. In the sixth Cr3+ site, Cr3+ is bonded to six O2- atoms to form CrO6 octahedra that share a cornercorner with one ZnO4 tetrahedra, corners with five CrO4 tetrahedra, edges with three CrO6 octahedra, and edges with three ZnO6 octahedra. There are a spread of Cr–O bond distances ranging from 2.02–2.05 Å. In the seventh Cr3+ site, Cr3+ is bonded to four O2- atoms to form CrO4 tetrahedra that share corners with six CrO6 octahedra and corners with six ZnO6 octahedra. The corner-sharing octahedra tilt angles range from 52–67°. There are a spread of Cr–O bond distances ranging from 1.90–2.00 Å. In the eighth Cr3+ site, Cr3+ is bonded to four O2- atoms to form CrO4 tetrahedra that share corners with six CrO6 octahedra and corners with six ZnO6 octahedra. The corner-sharing octahedra tilt angles range from 53–67°. There are a spread of Cr–O bond distances ranging from 1.91–2.02 Å. In the ninth Cr3+ site, Cr3+ is bonded to four O2- atoms to form CrO4 tetrahedra that share corners with three ZnO6 octahedra and corners with nine CrO6 octahedra. The corner-sharing octahedra tilt angles range from 54–66°. There are a spread of Cr–O bond distances ranging from 1.92–2.05 Å. There are six inequivalent Zn2+ sites. In the first Zn2+ site, Zn2+ is bonded to four O2- atoms to form ZnO4 tetrahedra that share corners with three ZnO6 octahedra and corners with nine CrO6 octahedra. The corner-sharing octahedra tilt angles range from 55–63°. There are a spread of Zn–O bond distances ranging from 1.98–2.05 Å. In the second Zn2+ site, Zn2+ is bonded to six O2- atoms to form ZnO6 octahedra that share corners with six CrO4 tetrahedra, edges with two ZnO6 octahedra, and edges with four CrO6 octahedra. There are a spread of Zn–O bond distances ranging from 2.12–2.14 Å. In the third Zn2+ site, Zn2+ is bonded to six O2- atoms to form ZnO6 octahedra that share corners with two equivalent ZnO4 tetrahedra, corners with four CrO4 tetrahedra, an edgeedge with one ZnO6 octahedra, and edges with five CrO6 octahedra. There are a spread of Zn–O bond distances ranging from 2.09–2.16 Å. In the fourth Zn2+ site, Zn2+ is bonded to six O2- atoms to form ZnO6 octahedra that share corners with six CrO4 tetrahedra, edges with two ZnO6 octahedra, and edges with four CrO6 octahedra. There are a spread of Zn–O bond distances ranging from 2.12–2.14 Å. In the fifth Zn2+ site, Zn2+ is bonded to six O2- atoms to form ZnO6 octahedra that share corners with six CrO4 tetrahedra, edges with two ZnO6 octahedra, and edges with four equivalent CrO6 octahedra. There are a spread of Zn–O bond distances ranging from 2.11–2.14 Å. In the sixth Zn2+ site, Zn2+ is bonded to six O2- atoms to form ZnO6 octahedra that share a cornercorner with one ZnO4 tetrahedra, corners with five CrO4 tetrahedra, an edgeedge with one ZnO6 octahedra, and edges with five CrO6 octahedra. There are a spread of Zn–O bond distances ranging from 2.03–2.18 Å. There are eighteen inequivalent O2- sites. In the first O2- site, O2- is bonded in a rectangular see-saw-like geometry to two Cr3+ and two Zn2+ atoms. In the second O2- site, O2- is bonded in a rectangular see-saw-like geometry to three Cr3+ and one Zn2+ atom. In the third O2- site, O2- is bonded in a rectangular see-saw-like geometry to three Cr3+ and one Zn2+ atom. In the fourth O2- site, O2- is bonded in a rectangular see-saw-like geometry to two Cr3+ and two Zn2+ atoms. In the fifth O2- site, O2- is bonded in a rectangular see-saw-like geometry to three Cr3+ and one Zn2+ atom. In the sixth O2- site, O2- is bonded in a rectangular see-saw-like geometry to three Cr3+ and one Zn2+ atom. In the seventh O2- site, O2- is bonded in a rectangular see-saw-like geometry to two Cr3+ and two Zn2+ atoms. In the eighth O2- site, O2- is bonded in a rectangular see-saw-like geometry to three Cr3+ and one Zn2+ atom. In the ninth O2- site, O2- is bonded in a rectangular see-saw-like geometry to three Cr3+ and one Zn2+ atom. In the tenth O2- site, O2- is bonded in a rectangular see-saw-like geometry to two Cr3+ and two Zn2+ atoms. In the eleventh O2- site, O2- is bonded in a rectangular see-saw-like geometry to three Cr3+ and one Zn2+ atom. In the twelfth O2- site, O2- is bonded in a rectangular see-saw-like geometry to two Cr3+ and two Zn2+ atoms. In the thirteenth O2- site, O2- is bonded in a rectangular see-saw-like geometry to two equivalent Cr3+ and two Zn2+ atoms. In the fourteenth O2- site, O2- is bonded in a rectangular see-saw-like geometry to three Cr3+ and one Zn2+ atom. In the fifteenth O2- site, O2- is bonded in a rectangular see-saw-like geometry to three Cr3+ and one Zn2+ atom. In the sixteenth O2- site, O2- is bonded in a rectangular see-saw-like geometry to four Cr3+ atoms. In the seventeenth O2- site, O2- is bonded in a rectangular see-saw-like geometry to three Cr3+ and one Zn2+ atom. In the eighteenth O2- site, O2- is bonded in a rectangular see-saw-like geometry to three Cr3+ and one Zn2+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on ZnCrO4 by Materials Project

Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

36 MATERIALS SCIENCE↗