MgSiO3 crystallizes in the monoclinic C2/c space group. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to two equivalent O(3) and four equivalent O(1) atoms to form MgO6 octahedra that share corners with four equivalent Si(1)O6 octahedra, edges with two equivalent Mg(1)O6 octahedra, and edges with four equivalent Si(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 13-23°. In the second Mg site, Mg(2) is bonded in a 6-coordinate geometry to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms. Si(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form SiO6 octahedra that share corners with two equivalent Mg(1)O6 octahedra, edges with two equivalent Mg(1)O6 octahedra, and edges with three equivalent Si(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 13-23°. There are three inequivalent O sites. In the first O site, O(1) is bonded to one Mg(2), two equivalent Mg(1), and two equivalent Si(1) atoms to form a mixture of distorted corner and edge-sharing OMg3Si2 square pyramids. In the second O site, O(2) is bonded in a distorted T-shaped geometry to one Mg(2) and two equivalent Si(1) atoms. In the third O site, O(3) is bonded in a see-saw-like geometry to one Mg(1), one Mg(2), and two equivalent Si(1) atoms.
MgSiO3 crystallizes in the monoclinic C2/c space group. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to two equivalent O(3) and four equivalent O(1) atoms to form MgO6 octahedra that share corners with four equivalent Si(1)O6 octahedra, edges with two equivalent Mg(1)O6 octahedra, and edges with four equivalent Si(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 13-23°. Both Mg(1)-O(3) bond lengths are 2.03 Å. There are two shorter (2.09 Å) and two longer (2.15 Å) Mg(1)-O(1) bond lengths. In the second Mg site, Mg(2) is bonded in a 6-coordinate geometry to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms. Both Mg(2)-O(1) bond lengths are 2.47 Å. Both Mg(2)-O(2) bond lengths are 1.96 Å. Both Mg(2)-O(3) bond lengths are 2.02 Å. Si(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form SiO6 octahedra that share corners with two equivalent Mg(1)O6 octahedra, edges with two equivalent Mg(1)O6 octahedra, and edges with three equivalent Si(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 13-23°. Both Si(1)-O(1) bond lengths are 1.89 Å. There is one shorter (1.72 Å) and one longer (1.77 Å) Si(1)-O(2) bond length. There is one shorter (1.82 Å) and one longer (1.85 Å) Si(1)-O(3) bond length. There are three inequivalent O sites. In the first O site, O(1) is bonded to one Mg(2), two equivalent Mg(1), and two equivalent Si(1) atoms to form a mixture of distorted corner and edge-sharing OMg3Si2 square pyramids. In the second O site, O(2) is bonded in a distorted T-shaped geometry to one Mg(2) and two equivalent Si(1) atoms. In the third O site, O(3) is bonded in a see-saw-like geometry to one Mg(1), one Mg(2), and two equivalent Si(1) atoms.