Cr(SiO3)2 crystallizes in the monoclinic C2/c space group. Cr(1) is bonded to two equivalent O(2) and four equivalent O(3) atoms to form distorted CrO6 octahedra that share corners with six equivalent Si(1)O4 tetrahedra and edges with two equivalent Cr(1)O6 octahedra. Si(1) is bonded to one O(2), one O(3), and two equivalent O(1) atoms to form SiO4 tetrahedra that share corners with three equivalent Cr(1)O6 octahedra and corners with two equivalent Si(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 33-59°. There are three inequivalent O sites. In the first O site, O(1) is bonded in a bent 150 degrees geometry to two equivalent Si(1) atoms. In the second O site, O(2) is bonded in a bent 150 degrees geometry to one Cr(1) and one Si(1) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to two equivalent Cr(1) and one Si(1) atom.
Cr(SiO3)2 crystallizes in the monoclinic C2/c space group. Cr(1) is bonded to two equivalent O(2) and four equivalent O(3) atoms to form distorted CrO6 octahedra that share corners with six equivalent Si(1)O4 tetrahedra and edges with two equivalent Cr(1)O6 octahedra. Both Cr(1)-O(2) bond lengths are 1.86 Å. There are two shorter (1.95 Å) and two longer (2.10 Å) Cr(1)-O(3) bond lengths. Si(1) is bonded to one O(2), one O(3), and two equivalent O(1) atoms to form SiO4 tetrahedra that share corners with three equivalent Cr(1)O6 octahedra and corners with two equivalent Si(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 33-59°. The Si(1)-O(2) bond length is 1.62 Å. The Si(1)-O(3) bond length is 1.68 Å. Both Si(1)-O(1) bond lengths are 1.62 Å. There are three inequivalent O sites. In the first O site, O(1) is bonded in a bent 150 degrees geometry to two equivalent Si(1) atoms. In the second O site, O(2) is bonded in a bent 150 degrees geometry to one Cr(1) and one Si(1) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to two equivalent Cr(1) and one Si(1) atom.