SrU(SeO4)2 crystallizes in the triclinic P-1 space group. Sr(1) is bonded in a 8-coordinate geometry to one O(5), one O(6), two equivalent O(4), two equivalent O(7), and two equivalent O(8) atoms. U(1) is bonded in a 7-coordinate geometry to one O(2), one O(3), one O(5), one O(6), one O(8), and two equivalent O(1) atoms. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded in a trigonal non-coplanar geometry to one O(1), one O(2), and one O(5) atom. In the second Se site, Se(2) is bonded in a distorted trigonal non-coplanar geometry to one O(4), one O(7), and one O(8) atom. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to two equivalent U(1) and one Se(1) atom. In the second O site, O(2) is bonded in a distorted bent 120 degrees geometry to one U(1) and one Se(1) atom. In the third O site, O(3) is bonded in a single-bond geometry to one U(1) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to two equivalent Sr(1) and one Se(2) atom. In the fifth O site, O(5) is bonded in a distorted trigonal non-coplanar geometry to one Sr(1), one U(1), and one Se(1) atom. In the sixth O site, O(6) is bonded in a distorted bent 150 degrees geometry to one Sr(1) and one U(1) atom. In the seventh O site, O(7) is bonded in a distorted trigonal non-coplanar geometry to two equivalent Sr(1) and one Se(2) atom. In the eighth O site, O(8) is bonded in a 4-coordinate geometry to two equivalent Sr(1), one U(1), and one Se(2) atom.
SrU(SeO4)2 crystallizes in the triclinic P-1 space group. Sr(1) is bonded in a 8-coordinate geometry to one O(5), one O(6), two equivalent O(4), two equivalent O(7), and two equivalent O(8) atoms. The Sr(1)-O(5) bond length is 2.62 Å. The Sr(1)-O(6) bond length is 2.71 Å. There is one shorter (2.51 Å) and one longer (2.54 Å) Sr(1)-O(4) bond length. There is one shorter (2.47 Å) and one longer (2.57 Å) Sr(1)-O(7) bond length. There is one shorter (2.75 Å) and one longer (2.99 Å) Sr(1)-O(8) bond length. U(1) is bonded in a 7-coordinate geometry to one O(2), one O(3), one O(5), one O(6), one O(8), and two equivalent O(1) atoms. The U(1)-O(2) bond length is 2.34 Å. The U(1)-O(3) bond length is 1.81 Å. The U(1)-O(5) bond length is 2.48 Å. The U(1)-O(6) bond length is 1.84 Å. The U(1)-O(8) bond length is 2.31 Å. There is one shorter (2.37 Å) and one longer (2.65 Å) U(1)-O(1) bond length. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded in a trigonal non-coplanar geometry to one O(1), one O(2), and one O(5) atom. The Se(1)-O(1) bond length is 1.76 Å. The Se(1)-O(2) bond length is 1.73 Å. The Se(1)-O(5) bond length is 1.73 Å. In the second Se site, Se(2) is bonded in a distorted trigonal non-coplanar geometry to one O(4), one O(7), and one O(8) atom. The Se(2)-O(4) bond length is 1.70 Å. The Se(2)-O(7) bond length is 1.70 Å. The Se(2)-O(8) bond length is 1.82 Å. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to two equivalent U(1) and one Se(1) atom. In the second O site, O(2) is bonded in a distorted bent 120 degrees geometry to one U(1) and one Se(1) atom. In the third O site, O(3) is bonded in a single-bond geometry to one U(1) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to two equivalent Sr(1) and one Se(2) atom. In the fifth O site, O(5) is bonded in a distorted trigonal non-coplanar geometry to one Sr(1), one U(1), and one Se(1) atom. In the sixth O site, O(6) is bonded in a distorted bent 150 degrees geometry to one Sr(1) and one U(1) atom. In the seventh O site, O(7) is bonded in a distorted trigonal non-coplanar geometry to two equivalent Sr(1) and one Se(2) atom. In the eighth O site, O(8) is bonded in a 4-coordinate geometry to two equivalent Sr(1), one U(1), and one Se(2) atom.