Sr2CoSe2(O3Cl)2 crystallizes in the monoclinic P2_1/c space group. Sr(1) is bonded in a 8-coordinate geometry to two equivalent O(1), two equivalent O(2), two equivalent O(3), and two equivalent Cl(1) atoms. Co(1) is bonded in an octahedral geometry to two equivalent O(1), two equivalent O(3), and two equivalent Cl(1) atoms. Se(1) is bonded in a distorted trigonal non-coplanar geometry to one O(1), one O(2), and one O(3) atom. There are three inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Sr(1), one Co(1), and one Se(1) atom to form distorted corner-sharing OSr2CoSe tetrahedra. In the second O site, O(2) is bonded in a 3-coordinate geometry to two equivalent Sr(1) and one Se(1) atom. In the third O site, O(3) is bonded in a 4-coordinate geometry to two equivalent Sr(1), one Co(1), and one Se(1) atom. Cl(1) is bonded in a 3-coordinate geometry to two equivalent Sr(1) and one Co(1) atom.
Sr2CoSe2(O3Cl)2 crystallizes in the monoclinic P2_1/c space group. Sr(1) is bonded in a 8-coordinate geometry to two equivalent O(1), two equivalent O(2), two equivalent O(3), and two equivalent Cl(1) atoms. There is one shorter (2.62 Å) and one longer (2.90 Å) Sr(1)-O(1) bond length. There is one shorter (2.54 Å) and one longer (2.66 Å) Sr(1)-O(2) bond length. There is one shorter (2.72 Å) and one longer (2.81 Å) Sr(1)-O(3) bond length. There is one shorter (3.05 Å) and one longer (3.19 Å) Sr(1)-Cl(1) bond length. Co(1) is bonded in an octahedral geometry to two equivalent O(1), two equivalent O(3), and two equivalent Cl(1) atoms. Both Co(1)-O(1) bond lengths are 2.12 Å. Both Co(1)-O(3) bond lengths are 2.11 Å. Both Co(1)-Cl(1) bond lengths are 2.51 Å. Se(1) is bonded in a distorted trigonal non-coplanar geometry to one O(1), one O(2), and one O(3) atom. The Se(1)-O(1) bond length is 1.75 Å. The Se(1)-O(2) bond length is 1.70 Å. The Se(1)-O(3) bond length is 1.76 Å. There are three inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Sr(1), one Co(1), and one Se(1) atom to form distorted corner-sharing OSr2CoSe tetrahedra. In the second O site, O(2) is bonded in a 3-coordinate geometry to two equivalent Sr(1) and one Se(1) atom. In the third O site, O(3) is bonded in a 4-coordinate geometry to two equivalent Sr(1), one Co(1), and one Se(1) atom. Cl(1) is bonded in a 3-coordinate geometry to two equivalent Sr(1) and one Co(1) atom.