V4Si4O13 crystallizes in the triclinic P-1 space group. There are four inequivalent V sites. In the first V site, V(1) is bonded to one O(1), one O(3), one O(4), one O(6), and two equivalent O(2) atoms to form distorted VO6 octahedra that share  a cornercorner with one Si(2)O4 tetrahedra,  a cornercorner with one Si(3)O4 tetrahedra, corners with two equivalent Si(1)O4 tetrahedra, corners with two equivalent Si(4)O4 tetrahedra,  an edgeedge with one V(1)O6 octahedra, and edges with three equivalent V(2)O6 octahedra. In the second V site, V(2) is bonded to one O(2), one O(3), one O(5), one O(6), and two equivalent O(1) atoms to form VO6 octahedra that share  a cornercorner with one V(3)O6 octahedra,  a cornercorner with one Si(2)O4 tetrahedra,  a cornercorner with one Si(4)O4 tetrahedra, corners with two equivalent Si(1)O4 tetrahedra, corners with two equivalent Si(3)O4 tetrahedra,  an edgeedge with one V(2)O6 octahedra, and edges with three equivalent V(1)O6 octahedra. The corner-sharing octahedral tilt angles are 55°. In the third V site, V(3) is bonded to one O(10), one O(5), one O(8), one O(9), and two equivalent O(7) atoms to form VO6 octahedra that share  a cornercorner with one V(2)O6 octahedra,  a cornercorner with one Si(2)O4 tetrahedra,  a cornercorner with one Si(4)O4 tetrahedra, corners with two equivalent Si(3)O4 tetrahedra,  an edgeedge with one V(3)O6 octahedra, and  an edgeedge with one Si(1)O4 tetrahedra. The corner-sharing octahedral tilt angles are 55°. In the fourth V site, V(4) is bonded in a 6-coordinate geometry to one O(10), one O(4), one O(7), one O(9), and two equivalent O(8) atoms. There are four inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(3), one O(4), one O(5), and one O(9) atom to form SiO4 tetrahedra that share corners with two equivalent V(1)O6 octahedra, corners with two equivalent V(2)O6 octahedra, and  an edgeedge with one V(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 50-61°. In the second Si site, Si(2) is bonded to one O(10), one O(12), one O(13), and one O(6) atom to form SiO4 tetrahedra that share  a cornercorner with one V(1)O6 octahedra,  a cornercorner with one V(2)O6 octahedra,  a cornercorner with one V(3)O6 octahedra,  a cornercorner with one Si(3)O4 tetrahedra, and  a cornercorner with one Si(4)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 55-63°. In the third Si site, Si(3) is bonded to one O(1), one O(11), one O(12), and one O(7) atom to form SiO4 tetrahedra that share  a cornercorner with one V(1)O6 octahedra, corners with two equivalent V(2)O6 octahedra, corners with two equivalent V(3)O6 octahedra,  a cornercorner with one Si(2)O4 tetrahedra, and  a cornercorner with one Si(4)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 49-68°. In the fourth Si site, Si(4) is bonded to one O(11), one O(13), one O(2), and one O(8) atom to form SiO4 tetrahedra that share  a cornercorner with one V(2)O6 octahedra,  a cornercorner with one V(3)O6 octahedra, corners with two equivalent V(1)O6 octahedra,  a cornercorner with one Si(2)O4 tetrahedra, and  a cornercorner with one Si(3)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 48-66°. There are thirteen inequivalent O sites. In the first O site, O(1) is bonded to one V(1), two equivalent V(2), and one Si(3) atom to form a mixture of distorted edge and corner-sharing OV3Si tetrahedra. In the second O site, O(2) is bonded to one V(2), two equivalent V(1), and one Si(4) atom to form a mixture of distorted edge and corner-sharing OV3Si tetrahedra. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one V(1), one V(2), and one Si(1) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one V(1), one V(4), and one Si(1) atom. In the fifth O site, O(5) is bonded in a distorted trigonal planar geometry to one V(2), one V(3), and one Si(1) atom. In the sixth O site, O(6) is bonded in a distorted trigonal non-coplanar geometry to one V(1), one V(2), and one Si(2) atom. In the seventh O site, O(7) is bonded in a 4-coordinate geometry to one V(4), two equivalent V(3), and one Si(3) atom. In the eighth O site, O(8) is bonded to one V(3), two equivalent V(4), and one Si(4) atom to form a mixture of distorted edge and corner-sharing OV3Si trigonal pyramids. In the ninth O site, O(9) is bonded in a distorted trigonal non-coplanar geometry to one V(3), one V(4), and one Si(1) atom. In the tenth O site, O(10) is bonded in a trigonal planar geometry to one V(3), one V(4), and one Si(2) atom. In the eleventh O site, O(11) is bonded in a bent 150 degrees geometry to one Si(3) and one Si(4) atom. In the twelfth O site, O(12) is bonded in a distorted bent 120 degrees geometry to one Si(2) and one Si(3) atom. In the thirteenth O site, O(13) is bonded in a bent 120 degrees geometry to one Si(2) and one Si(4) atom.
V4Si4O13 crystallizes in the triclinic P-1 space group. There are four inequivalent V sites. In the first V site, V(1) is bonded to one O(1), one O(3), one O(4), one O(6), and two equivalent O(2) atoms to form distorted VO6 octahedra that share  a cornercorner with one Si(2)O4 tetrahedra,  a cornercorner with one Si(3)O4 tetrahedra, corners with two equivalent Si(1)O4 tetrahedra, corners with two equivalent Si(4)O4 tetrahedra,  an edgeedge with one V(1)O6 octahedra, and edges with three equivalent V(2)O6 octahedra. The V(1)-O(1) bond length is 2.23 Å. The V(1)-O(3) bond length is 2.02 Å. The V(1)-O(4) bond length is 1.96 Å. The V(1)-O(6) bond length is 2.08 Å. There is one shorter (2.19 Å) and one longer (2.31 Å) V(1)-O(2) bond length. In the second V site, V(2) is bonded to one O(2), one O(3), one O(5), one O(6), and two equivalent O(1) atoms to form VO6 octahedra that share  a cornercorner with one V(3)O6 octahedra,  a cornercorner with one Si(2)O4 tetrahedra,  a cornercorner with one Si(4)O4 tetrahedra, corners with two equivalent Si(1)O4 tetrahedra, corners with two equivalent Si(3)O4 tetrahedra,  an edgeedge with one V(2)O6 octahedra, and edges with three equivalent V(1)O6 octahedra. The corner-sharing octahedral tilt angles are 55°. The V(2)-O(2) bond length is 2.27 Å. The V(2)-O(3) bond length is 2.27 Å. The V(2)-O(5) bond length is 2.11 Å. The V(2)-O(6) bond length is 2.21 Å. There is one shorter (2.23 Å) and one longer (2.24 Å) V(2)-O(1) bond length. In the third V site, V(3) is bonded to one O(10), one O(5), one O(8), one O(9), and two equivalent O(7) atoms to form VO6 octahedra that share  a cornercorner with one V(2)O6 octahedra,  a cornercorner with one Si(2)O4 tetrahedra,  a cornercorner with one Si(4)O4 tetrahedra, corners with two equivalent Si(3)O4 tetrahedra,  an edgeedge with one V(3)O6 octahedra, and  an edgeedge with one Si(1)O4 tetrahedra. The corner-sharing octahedral tilt angles are 55°. The V(3)-O(10) bond length is 2.03 Å. The V(3)-O(5) bond length is 2.02 Å. The V(3)-O(8) bond length is 2.14 Å. The V(3)-O(9) bond length is 2.11 Å. There is one shorter (2.14 Å) and one longer (2.15 Å) V(3)-O(7) bond length. In the fourth V site, V(4) is bonded in a 6-coordinate geometry to one O(10), one O(4), one O(7), one O(9), and two equivalent O(8) atoms. The V(4)-O(10) bond length is 2.18 Å. The V(4)-O(4) bond length is 2.16 Å. The V(4)-O(7) bond length is 2.51 Å. The V(4)-O(9) bond length is 2.15 Å. There is one shorter (2.20 Å) and one longer (2.35 Å) V(4)-O(8) bond length. There are four inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(3), one O(4), one O(5), and one O(9) atom to form SiO4 tetrahedra that share corners with two equivalent V(1)O6 octahedra, corners with two equivalent V(2)O6 octahedra, and  an edgeedge with one V(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 50-61°. The Si(1)-O(3) bond length is 1.64 Å. The Si(1)-O(4) bond length is 1.68 Å. The Si(1)-O(5) bond length is 1.67 Å. The Si(1)-O(9) bond length is 1.65 Å. In the second Si site, Si(2) is bonded to one O(10), one O(12), one O(13), and one O(6) atom to form SiO4 tetrahedra that share  a cornercorner with one V(1)O6 octahedra,  a cornercorner with one V(2)O6 octahedra,  a cornercorner with one V(3)O6 octahedra,  a cornercorner with one Si(3)O4 tetrahedra, and  a cornercorner with one Si(4)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 55-63°. The Si(2)-O(10) bond length is 1.63 Å. The Si(2)-O(12) bond length is 1.63 Å. The Si(2)-O(13) bond length is 1.63 Å. The Si(2)-O(6) bond length is 1.63 Å. In the third Si site, Si(3) is bonded to one O(1), one O(11), one O(12), and one O(7) atom to form SiO4 tetrahedra that share  a cornercorner with one V(1)O6 octahedra, corners with two equivalent V(2)O6 octahedra, corners with two equivalent V(3)O6 octahedra,  a cornercorner with one Si(2)O4 tetrahedra, and  a cornercorner with one Si(4)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 49-68°. The Si(3)-O(1) bond length is 1.65 Å. The Si(3)-O(11) bond length is 1.59 Å. The Si(3)-O(12) bond length is 1.61 Å. The Si(3)-O(7) bond length is 1.66 Å. In the fourth Si site, Si(4) is bonded to one O(11), one O(13), one O(2), and one O(8) atom to form SiO4 tetrahedra that share  a cornercorner with one V(2)O6 octahedra,  a cornercorner with one V(3)O6 octahedra, corners with two equivalent V(1)O6 octahedra,  a cornercorner with one Si(2)O4 tetrahedra, and  a cornercorner with one Si(3)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 48-66°. The Si(4)-O(11) bond length is 1.59 Å. The Si(4)-O(13) bond length is 1.62 Å. The Si(4)-O(2) bond length is 1.66 Å. The Si(4)-O(8) bond length is 1.65 Å. There are thirteen inequivalent O sites. In the first O site, O(1) is bonded to one V(1), two equivalent V(2), and one Si(3) atom to form a mixture of distorted edge and corner-sharing OV3Si tetrahedra. In the second O site, O(2) is bonded to one V(2), two equivalent V(1), and one Si(4) atom to form a mixture of distorted edge and corner-sharing OV3Si tetrahedra. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one V(1), one V(2), and one Si(1) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one V(1), one V(4), and one Si(1) atom. In the fifth O site, O(5) is bonded in a distorted trigonal planar geometry to one V(2), one V(3), and one Si(1) atom. In the sixth O site, O(6) is bonded in a distorted trigonal non-coplanar geometry to one V(1), one V(2), and one Si(2) atom. In the seventh O site, O(7) is bonded in a 4-coordinate geometry to one V(4), two equivalent V(3), and one Si(3) atom. In the eighth O site, O(8) is bonded to one V(3), two equivalent V(4), and one Si(4) atom to form a mixture of distorted edge and corner-sharing OV3Si trigonal pyramids. In the ninth O site, O(9) is bonded in a distorted trigonal non-coplanar geometry to one V(3), one V(4), and one Si(1) atom. In the tenth O site, O(10) is bonded in a trigonal planar geometry to one V(3), one V(4), and one Si(2) atom. In the eleventh O site, O(11) is bonded in a bent 150 degrees geometry to one Si(3) and one Si(4) atom. In the twelfth O site, O(12) is bonded in a distorted bent 120 degrees geometry to one Si(2) and one Si(3) atom. In the thirteenth O site, O(13) is bonded in a bent 120 degrees geometry to one Si(2) and one Si(4) atom.