CaV(SiO3)2 is Esseneite structured and crystallizes in the monoclinic C2/c space group. Ca(1) is bonded in a 8-coordinate geometry to two equivalent O(2), two equivalent O(3), and four equivalent O(1) atoms. V(1) is bonded to two equivalent O(2) and four equivalent O(3) atoms to form VO6 octahedra that share corners with six equivalent Si(1)O4 tetrahedra and edges with two equivalent V(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 V(1)O6 octahedra and corners with two equivalent Si(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 34-57°. There are three inequivalent O sites. In the first O site, O(1) is bonded in a 2-coordinate geometry to two equivalent Ca(1) and two equivalent Si(1) atoms. In the second O site, O(2) is bonded in a distorted T-shaped geometry to one Ca(1), one V(1), and one Si(1) atom. In the third O site, O(3) is bonded to one Ca(1), two equivalent V(1), and one Si(1) atom to form a mixture of distorted corner and edge-sharing OCaV2Si trigonal pyramids.
CaV(SiO3)2 is Esseneite structured and crystallizes in the monoclinic C2/c space group. Ca(1) is bonded in a 8-coordinate geometry to two equivalent O(2), two equivalent O(3), and four equivalent O(1) atoms. Both Ca(1)-O(2) bond lengths are 2.34 Å. Both Ca(1)-O(3) bond lengths are 2.38 Å. There are two shorter (2.67 Å) and two longer (2.81 Å) Ca(1)-O(1) bond lengths. V(1) is bonded to two equivalent O(2) and four equivalent O(3) atoms to form VO6 octahedra that share corners with six equivalent Si(1)O4 tetrahedra and edges with two equivalent V(1)O6 octahedra. Both V(1)-O(2) bond lengths are 2.14 Å. There are two shorter (2.17 Å) and two longer (2.20 Å) V(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 V(1)O6 octahedra and corners with two equivalent Si(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 34-57°. The Si(1)-O(2) bond length is 1.60 Å. The Si(1)-O(3) bond length is 1.62 Å. There is one shorter (1.68 Å) and one longer (1.70 Å) Si(1)-O(1) bond length. There are three inequivalent O sites. In the first O site, O(1) is bonded in a 2-coordinate geometry to two equivalent Ca(1) and two equivalent Si(1) atoms. In the second O site, O(2) is bonded in a distorted T-shaped geometry to one Ca(1), one V(1), and one Si(1) atom. In the third O site, O(3) is bonded to one Ca(1), two equivalent V(1), and one Si(1) atom to form a mixture of distorted corner and edge-sharing OCaV2Si trigonal pyramids.