Ni3Se3O10 crystallizes in the triclinic P-1 space group. There are four inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to one O(2), one O(3), one O(6), one O(8), and two equivalent O(10) atoms to form a mixture of edge and corner-sharing NiO6 octahedra. The corner-sharing octahedral tilt angles range from 48-61°. In the second Ni site, Ni(2) is bonded to one O(1), one O(10), one O(5), one O(7), and two equivalent O(9) atoms to form a mixture of edge and corner-sharing NiO6 octahedra. The corner-sharing octahedral tilt angles range from 49-61°. In the third Ni site, Ni(3) is bonded to two equivalent O(1), two equivalent O(4), and two equivalent O(8) atoms to form corner-sharing NiO6 octahedra. The corner-sharing octahedral tilt angles range from 48-49°. In the fourth Ni site, Ni(4) is bonded to two equivalent O(3), two equivalent O(5), and two equivalent O(6) atoms to form a mixture of edge and corner-sharing NiO6 octahedra. The corner-sharing octahedral tilt angles are 50°. There are three inequivalent Se sites. In the first Se site, Se(1) is bonded in a distorted T-shaped geometry to one O(10), one O(6), and one O(8) atom. In the second Se site, Se(2) is bonded in a trigonal non-coplanar geometry to one O(3), one O(4), and one O(9) atom. In the third Se site, Se(3) is bonded in a trigonal non-coplanar geometry to one O(1), one O(2), and one O(5) atom. There are ten inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to one Ni(2), one Ni(3), and one Se(3) atom. In the second O site, O(2) is bonded in a bent 120 degrees geometry to one Ni(1) and one Se(3) atom. In the third O site, O(3) is bonded in a trigonal planar geometry to one Ni(1), one Ni(4), and one Se(2) atom. In the fourth O site, O(4) is bonded in a bent 150 degrees geometry to one Ni(3) and one Se(2) atom. In the fifth O site, O(5) is bonded in a distorted trigonal planar geometry to one Ni(2), one Ni(4), and one Se(3) atom. In the sixth O site, O(6) is bonded in a distorted trigonal non-coplanar geometry to one Ni(1), one Ni(4), and one Se(1) atom. In the seventh O site, O(7) is bonded in a single-bond geometry to one Ni(2) atom. In the eighth O site, O(8) is bonded in a trigonal planar geometry to one Ni(1), one Ni(3), and one Se(1) atom. In the ninth O site, O(9) is bonded in a trigonal non-coplanar geometry to two equivalent Ni(2) and one Se(2) atom. In the tenth O site, O(10) is bonded to one Ni(2), two equivalent Ni(1), and one Se(1) atom to form distorted edge-sharing ONi3Se trigonal pyramids.
Ni3Se3O10 crystallizes in the triclinic P-1 space group. There are four inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to one O(2), one O(3), one O(6), one O(8), and two equivalent O(10) atoms to form a mixture of edge and corner-sharing NiO6 octahedra. The corner-sharing octahedral tilt angles range from 48-61°. The Ni(1)-O(2) bond length is 2.03 Å. The Ni(1)-O(3) bond length is 2.05 Å. The Ni(1)-O(6) bond length is 2.08 Å. The Ni(1)-O(8) bond length is 2.03 Å. Both Ni(1)-O(10) bond lengths are 2.20 Å. In the second Ni site, Ni(2) is bonded to one O(1), one O(10), one O(5), one O(7), and two equivalent O(9) atoms to form a mixture of edge and corner-sharing NiO6 octahedra. The corner-sharing octahedral tilt angles range from 49-61°. The Ni(2)-O(1) bond length is 2.15 Å. The Ni(2)-O(10) bond length is 2.10 Å. The Ni(2)-O(5) bond length is 2.17 Å. The Ni(2)-O(7) bond length is 1.91 Å. There is one shorter (2.06 Å) and one longer (2.09 Å) Ni(2)-O(9) bond length. In the third Ni site, Ni(3) is bonded to two equivalent O(1), two equivalent O(4), and two equivalent O(8) atoms to form corner-sharing NiO6 octahedra. The corner-sharing octahedral tilt angles range from 48-49°. Both Ni(3)-O(1) bond lengths are 2.17 Å. Both Ni(3)-O(4) bond lengths are 2.07 Å. Both Ni(3)-O(8) bond lengths are 2.02 Å. In the fourth Ni site, Ni(4) is bonded to two equivalent O(3), two equivalent O(5), and two equivalent O(6) atoms to form a mixture of edge and corner-sharing NiO6 octahedra. The corner-sharing octahedral tilt angles are 50°. Both Ni(4)-O(3) bond lengths are 2.11 Å. Both Ni(4)-O(5) bond lengths are 2.07 Å. Both Ni(4)-O(6) bond lengths are 2.11 Å. There are three inequivalent Se sites. In the first Se site, Se(1) is bonded in a distorted T-shaped geometry to one O(10), one O(6), and one O(8) atom. The Se(1)-O(10) bond length is 1.79 Å. The Se(1)-O(6) bond length is 1.73 Å. The Se(1)-O(8) bond length is 1.74 Å. In the second Se site, Se(2) is bonded in a trigonal non-coplanar geometry to one O(3), one O(4), and one O(9) atom. The Se(2)-O(3) bond length is 1.75 Å. The Se(2)-O(4) bond length is 1.69 Å. The Se(2)-O(9) bond length is 1.76 Å. In the third Se site, Se(3) is bonded in a trigonal non-coplanar geometry to one O(1), one O(2), and one O(5) atom. The Se(3)-O(1) bond length is 1.73 Å. The Se(3)-O(2) bond length is 1.73 Å. The Se(3)-O(5) bond length is 1.76 Å. There are ten inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to one Ni(2), one Ni(3), and one Se(3) atom. In the second O site, O(2) is bonded in a bent 120 degrees geometry to one Ni(1) and one Se(3) atom. In the third O site, O(3) is bonded in a trigonal planar geometry to one Ni(1), one Ni(4), and one Se(2) atom. In the fourth O site, O(4) is bonded in a bent 150 degrees geometry to one Ni(3) and one Se(2) atom. In the fifth O site, O(5) is bonded in a distorted trigonal planar geometry to one Ni(2), one Ni(4), and one Se(3) atom. In the sixth O site, O(6) is bonded in a distorted trigonal non-coplanar geometry to one Ni(1), one Ni(4), and one Se(1) atom. In the seventh O site, O(7) is bonded in a single-bond geometry to one Ni(2) atom. In the eighth O site, O(8) is bonded in a trigonal planar geometry to one Ni(1), one Ni(3), and one Se(1) atom. In the ninth O site, O(9) is bonded in a trigonal non-coplanar geometry to two equivalent Ni(2) and one Se(2) atom. In the tenth O site, O(10) is bonded to one Ni(2), two equivalent Ni(1), and one Se(1) atom to form distorted edge-sharing ONi3Se trigonal pyramids.