CsVSeO5 crystallizes in the monoclinic P2_1 space group. There are two inequivalent Cs sites. In the first Cs site, Cs(1) is bonded in a 9-coordinate geometry to one O(1), one O(10), one O(3), one O(4), one O(9), two equivalent O(6), and two equivalent O(7) atoms. In the second Cs site, Cs(2) is bonded in a 9-coordinate geometry to one O(10), one O(3), one O(5), one O(6), one O(9), two equivalent O(1), and two equivalent O(2) atoms. There are two inequivalent V sites. In the first V site, V(1) is bonded in a distorted trigonal bipyramidal geometry to one O(1), one O(2), one O(3), one O(4), and one O(5) atom. In the second V site, V(2) is bonded in a 5-coordinate geometry to one O(10), one O(6), one O(7), one O(8), and one O(9) atom. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded in a distorted trigonal non-coplanar geometry to one O(10), one O(4), and one O(5) atom. In the second Se site, Se(2) is bonded in a distorted trigonal non-coplanar geometry to one O(2), one O(8), and one O(9) atom. There are ten inequivalent O sites. In the first O site, O(1) is bonded in a single-bond geometry to one Cs(1), two equivalent Cs(2), and one V(1) atom. In the second O site, O(2) is bonded in a bent 120 degrees geometry to two equivalent Cs(2), one V(1), and one Se(2) atom. In the third O site, O(3) is bonded in a distorted single-bond geometry to one Cs(1), one Cs(2), and one V(1) atom. In the fourth O site, O(4) is bonded in a distorted bent 120 degrees geometry to one Cs(1), one V(1), and one Se(1) atom. In the fifth O site, O(5) is bonded in a distorted bent 120 degrees geometry to one Cs(2), one V(1), and one Se(1) atom. In the sixth O site, O(6) is bonded in a single-bond geometry to one Cs(2), two equivalent Cs(1), and one V(2) atom. In the seventh O site, O(7) is bonded in a distorted single-bond geometry to two equivalent Cs(1) and one V(2) atom. In the eighth O site, O(8) is bonded in a bent 120 degrees geometry to one V(2) and one Se(2) atom. In the ninth O site, O(9) is bonded in a distorted bent 120 degrees geometry to one Cs(1), one Cs(2), one V(2), and one Se(2) atom. In the tenth O site, O(10) is bonded in a distorted bent 120 degrees geometry to one Cs(1), one Cs(2), one V(2), and one Se(1) atom.
CsVSeO5 crystallizes in the monoclinic P2_1 space group. There are two inequivalent Cs sites. In the first Cs site, Cs(1) is bonded in a 9-coordinate geometry to one O(1), one O(10), one O(3), one O(4), one O(9), two equivalent O(6), and two equivalent O(7) atoms. The Cs(1)-O(1) bond length is 3.38 Å. The Cs(1)-O(10) bond length is 3.16 Å. The Cs(1)-O(3) bond length is 3.13 Å. The Cs(1)-O(4) bond length is 3.15 Å. The Cs(1)-O(9) bond length is 3.49 Å. There is one shorter (3.14 Å) and one longer (3.18 Å) Cs(1)-O(6) bond length. There is one shorter (3.04 Å) and one longer (3.48 Å) Cs(1)-O(7) bond length. In the second Cs site, Cs(2) is bonded in a 9-coordinate geometry to one O(10), one O(3), one O(5), one O(6), one O(9), two equivalent O(1), and two equivalent O(2) atoms. The Cs(2)-O(10) bond length is 3.33 Å. The Cs(2)-O(3) bond length is 3.20 Å. The Cs(2)-O(5) bond length is 3.15 Å. The Cs(2)-O(6) bond length is 3.06 Å. The Cs(2)-O(9) bond length is 3.34 Å. There is one shorter (3.08 Å) and one longer (3.17 Å) Cs(2)-O(1) bond length. There is one shorter (3.28 Å) and one longer (3.32 Å) Cs(2)-O(2) bond length. There are two inequivalent V sites. In the first V site, V(1) is bonded in a distorted trigonal bipyramidal geometry to one O(1), one O(2), one O(3), one O(4), and one O(5) atom. The V(1)-O(1) bond length is 1.64 Å. The V(1)-O(2) bond length is 1.96 Å. The V(1)-O(3) bond length is 1.66 Å. The V(1)-O(4) bond length is 1.99 Å. The V(1)-O(5) bond length is 1.98 Å. In the second V site, V(2) is bonded in a 5-coordinate geometry to one O(10), one O(6), one O(7), one O(8), and one O(9) atom. The V(2)-O(10) bond length is 1.96 Å. The V(2)-O(6) bond length is 1.63 Å. The V(2)-O(7) bond length is 1.66 Å. The V(2)-O(8) bond length is 1.96 Å. The V(2)-O(9) bond length is 2.04 Å. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded in a distorted trigonal non-coplanar geometry to one O(10), one O(4), and one O(5) atom. The Se(1)-O(10) bond length is 1.73 Å. The Se(1)-O(4) bond length is 1.72 Å. The Se(1)-O(5) bond length is 1.71 Å. In the second Se site, Se(2) is bonded in a distorted trigonal non-coplanar geometry to one O(2), one O(8), and one O(9) atom. The Se(2)-O(2) bond length is 1.72 Å. The Se(2)-O(8) bond length is 1.74 Å. The Se(2)-O(9) bond length is 1.70 Å. There are ten inequivalent O sites. In the first O site, O(1) is bonded in a single-bond geometry to one Cs(1), two equivalent Cs(2), and one V(1) atom. In the second O site, O(2) is bonded in a bent 120 degrees geometry to two equivalent Cs(2), one V(1), and one Se(2) atom. In the third O site, O(3) is bonded in a distorted single-bond geometry to one Cs(1), one Cs(2), and one V(1) atom. In the fourth O site, O(4) is bonded in a distorted bent 120 degrees geometry to one Cs(1), one V(1), and one Se(1) atom. In the fifth O site, O(5) is bonded in a distorted bent 120 degrees geometry to one Cs(2), one V(1), and one Se(1) atom. In the sixth O site, O(6) is bonded in a single-bond geometry to one Cs(2), two equivalent Cs(1), and one V(2) atom. In the seventh O site, O(7) is bonded in a distorted single-bond geometry to two equivalent Cs(1) and one V(2) atom. In the eighth O site, O(8) is bonded in a bent 120 degrees geometry to one V(2) and one Se(2) atom. In the ninth O site, O(9) is bonded in a distorted bent 120 degrees geometry to one Cs(1), one Cs(2), one V(2), and one Se(2) atom. In the tenth O site, O(10) is bonded in a distorted bent 120 degrees geometry to one Cs(1), one Cs(2), one V(2), and one Se(1) atom.