CaV4O15 crystallizes in the triclinic P1 space group. Ca(1) is bonded in a 6-coordinate geometry to one O(12), one O(15), one O(3), one O(4), one O(6), and one O(9) atom. There are four inequivalent V sites. In the first V site, V(1) is bonded to one O(13), one O(2), one O(7), one O(8), and one O(9) atom to form distorted VO5 trigonal bipyramids that share  a cornercorner with one V(2)O4 tetrahedra and corners with two equivalent V(4)O5 trigonal bipyramids. In the second V site, V(2) is bonded to one O(1), one O(10), one O(14), and one O(7) atom to form distorted corner-sharing VO4 tetrahedra. In the third V site, V(3) is bonded in a 5-coordinate geometry to one O(11), one O(13), one O(14), one O(2), and one O(7) atom. In the fourth V site, V(4) is bonded to one O(1), one O(12), one O(13), one O(14), and one O(8) atom to form distorted VO5 trigonal bipyramids that share corners with two equivalent V(2)O4 tetrahedra and corners with two equivalent V(1)O5 trigonal bipyramids. There are fifteen inequivalent O sites. In the first O site, O(1) is bonded in a bent 150 degrees geometry to one V(2) and one V(4) atom. In the second O site, O(2) is bonded in a bent 150 degrees geometry to one V(1) and one V(3) atom. In the third O site, O(3) is bonded in a bent 120 degrees geometry to one Ca(1) and one O(6) atom. In the fourth O site, O(4) is bonded in a water-like geometry to one Ca(1) and one O(5) atom. In the fifth O site, O(5) is bonded in a bent 120 degrees geometry to one O(15) and one O(4) atom. In the sixth O site, O(6) is bonded in a bent 150 degrees geometry to one Ca(1) and one O(3) atom. In the seventh O site, O(7) is bonded in a distorted trigonal non-coplanar geometry to one V(1), one V(2), and one V(3) atom. In the eighth O site, O(8) is bonded in a 2-coordinate geometry to one V(1) and one V(4) atom. In the ninth O site, O(9) is bonded in a linear geometry to one Ca(1) and one V(1) atom. In the tenth O site, O(10) is bonded in a single-bond geometry to one V(2) atom. In the eleventh O site, O(11) is bonded in a single-bond geometry to one V(3) atom. In the twelfth O site, O(12) is bonded in a linear geometry to one Ca(1) and one V(4) atom. In the thirteenth O site, O(13) is bonded in a distorted trigonal non-coplanar geometry to one V(1), one V(3), and one V(4) atom. In the fourteenth O site, O(14) is bonded in a distorted trigonal non-coplanar geometry to one V(2), one V(3), and one V(4) atom. In the fifteenth O site, O(15) is bonded in a bent 120 degrees geometry to one Ca(1) and one O(5) atom.
CaV4O15 crystallizes in the triclinic P1 space group. Ca(1) is bonded in a 6-coordinate geometry to one O(12), one O(15), one O(3), one O(4), one O(6), and one O(9) atom. The Ca(1)-O(12) bond length is 2.30 Å. The Ca(1)-O(15) bond length is 2.53 Å. The Ca(1)-O(3) bond length is 2.69 Å. The Ca(1)-O(4) bond length is 2.36 Å. The Ca(1)-O(6) bond length is 2.75 Å. The Ca(1)-O(9) bond length is 2.24 Å. There are four inequivalent V sites. In the first V site, V(1) is bonded to one O(13), one O(2), one O(7), one O(8), and one O(9) atom to form distorted VO5 trigonal bipyramids that share  a cornercorner with one V(2)O4 tetrahedra and corners with two equivalent V(4)O5 trigonal bipyramids. The V(1)-O(13) bond length is 1.92 Å. The V(1)-O(2) bond length is 1.93 Å. The V(1)-O(7) bond length is 2.16 Å. The V(1)-O(8) bond length is 1.90 Å. The V(1)-O(9) bond length is 1.68 Å. In the second V site, V(2) is bonded to one O(1), one O(10), one O(14), and one O(7) atom to form distorted corner-sharing VO4 tetrahedra. The V(2)-O(1) bond length is 1.75 Å. The V(2)-O(10) bond length is 1.61 Å. The V(2)-O(14) bond length is 1.85 Å. The V(2)-O(7) bond length is 1.83 Å. In the third V site, V(3) is bonded in a 5-coordinate geometry to one O(11), one O(13), one O(14), one O(2), and one O(7) atom. The V(3)-O(11) bond length is 1.61 Å. The V(3)-O(13) bond length is 2.08 Å. The V(3)-O(14) bond length is 1.96 Å. The V(3)-O(2) bond length is 1.75 Å. The V(3)-O(7) bond length is 1.93 Å. In the fourth V site, V(4) is bonded to one O(1), one O(12), one O(13), one O(14), and one O(8) atom to form distorted VO5 trigonal bipyramids that share corners with two equivalent V(2)O4 tetrahedra and corners with two equivalent V(1)O5 trigonal bipyramids. The V(4)-O(1) bond length is 1.86 Å. The V(4)-O(12) bond length is 1.65 Å. The V(4)-O(13) bond length is 1.88 Å. The V(4)-O(14) bond length is 2.02 Å. The V(4)-O(8) bond length is 1.77 Å. There are fifteen inequivalent O sites. In the first O site, O(1) is bonded in a bent 150 degrees geometry to one V(2) and one V(4) atom. In the second O site, O(2) is bonded in a bent 150 degrees geometry to one V(1) and one V(3) atom. In the third O site, O(3) is bonded in a bent 120 degrees geometry to one Ca(1) and one O(6) atom. The O(3)-O(6) bond length is 1.25 Å. In the fourth O site, O(4) is bonded in a water-like geometry to one Ca(1) and one O(5) atom. The O(4)-O(5) bond length is 1.38 Å. In the fifth O site, O(5) is bonded in a bent 120 degrees geometry to one O(15) and one O(4) atom. The O(5)-O(15) bond length is 1.32 Å. In the sixth O site, O(6) is bonded in a bent 150 degrees geometry to one Ca(1) and one O(3) atom. In the seventh O site, O(7) is bonded in a distorted trigonal non-coplanar geometry to one V(1), one V(2), and one V(3) atom. In the eighth O site, O(8) is bonded in a 2-coordinate geometry to one V(1) and one V(4) atom. In the ninth O site, O(9) is bonded in a linear geometry to one Ca(1) and one V(1) atom. In the tenth O site, O(10) is bonded in a single-bond geometry to one V(2) atom. In the eleventh O site, O(11) is bonded in a single-bond geometry to one V(3) atom. In the twelfth O site, O(12) is bonded in a linear geometry to one Ca(1) and one V(4) atom. In the thirteenth O site, O(13) is bonded in a distorted trigonal non-coplanar geometry to one V(1), one V(3), and one V(4) atom. In the fourteenth O site, O(14) is bonded in a distorted trigonal non-coplanar geometry to one V(2), one V(3), and one V(4) atom. In the fifteenth O site, O(15) is bonded in a bent 120 degrees geometry to one Ca(1) and one O(5) atom.