Materials Data on ZnCrSiO5 by Materials Project
CrZnSiO5 crystallizes in the triclinic P1 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 CrO6 octahedra that share corners with two equivalent CrO6 octahedra, corners with four SiO4 tetrahedra, and edges with two equivalent ZnO6 pentagonal pyramids. The corner-sharing octahedra tilt angles range from 39–40°. There are a spread of Cr–O bond distances ranging from 1.85–2.01 Å. In the second Cr4+ site, Cr4+ is bonded to six O2- atoms to form CrO6 octahedra that share corners with two equivalent CrO6 octahedra, a cornercorner with one ZnO6 pentagonal pyramid, corners with four SiO4 tetrahedra, and an edgeedge with one ZnO6 pentagonal pyramid. The corner-sharing octahedra tilt angles range from 39–40°. There are a spread of Cr–O bond distances ranging from 1.86–2.00 Å. There are two inequivalent Zn2+ sites. In the first Zn2+ site, Zn2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Zn–O bond distances ranging from 1.97–2.53 Å. In the second Zn2+ site, Zn2+ is bonded to six O2- atoms to form distorted ZnO6 pentagonal pyramids that share a cornercorner with one CrO6 octahedra, corners with three SiO4 tetrahedra, edges with three CrO6 octahedra, and an edgeedge with one SiO4 tetrahedra. The corner-sharing octahedral tilt angles are 48°. There are a spread of Zn–O bond distances ranging from 1.98–2.35 Å. There are two inequivalent Si4+ sites. In the first Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with four CrO6 octahedra and corners with two equivalent ZnO6 pentagonal pyramids. The corner-sharing octahedra tilt angles range from 32–50°. There are a spread of Si–O bond distances ranging from 1.63–1.67 Å. In the second Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with four CrO6 octahedra, a cornercorner with one ZnO6 pentagonal pyramid, and an edgeedge with one ZnO6 pentagonal pyramid. The corner-sharing octahedra tilt angles range from 32–49°. There are a spread of Si–O bond distances ranging from 1.63–1.67 Å. There are ten inequivalent O2- sites. In the first O2- site, O2- is bonded in a 3-coordinate geometry to one Cr4+, one Zn2+, and one Si4+ atom. In the second O2- site, O2- is bonded in a 4-coordinate geometry to one Cr4+, two Zn2+, and one Si4+ atom. In the third O2- site, O2- is bonded in a 3-coordinate geometry to one Cr4+, one Zn2+, and one Si4+ atom. In the fourth O2- site, O2- is bonded in a 4-coordinate geometry to one Cr4+, two Zn2+, and one Si4+ atom. In the fifth O2- site, O2- is bonded in a distorted T-shaped geometry to one Cr4+, one Zn2+, and one Si4+ atom. In the sixth O2- site, O2- is bonded in a 3-coordinate geometry to one Cr4+, one Zn2+, and one Si4+ atom. In the seventh O2- site, O2- is bonded in a 3-coordinate geometry to one Cr4+, one Zn2+, and one Si4+ atom. In the eighth O2- site, O2- is bonded in a 3-coordinate geometry to one Cr4+, one Zn2+, and one Si4+ atom. In the ninth O2- site, O2- is bonded in a distorted trigonal planar geometry to two Cr4+ and one Zn2+ atom. In the tenth O2- site, O2- is bonded in a distorted trigonal planar geometry to two Cr4+ and one Zn2+ atom.