Pr4Se3(O5F3)2 crystallizes in the monoclinic C2/c space group. There are two inequivalent Pr sites. In the first Pr site, Pr(1) is bonded in a 10-coordinate geometry to one O(4), one O(5), two equivalent O(3), one F(2), two equivalent F(1), and three equivalent F(3) atoms. In the second Pr site, Pr(2) is bonded in a 10-coordinate geometry to one O(2), one O(3), one O(4), one O(5), two equivalent O(1), one F(1), one F(3), and two equivalent F(2) 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(3), one O(4), and one O(5) atom. In the second Se site, Se(2) is bonded in a tetrahedral geometry to two equivalent O(1) and two equivalent O(2) atoms. There are five inequivalent O sites. In the first O site, O(4) is bonded in a distorted trigonal planar geometry to one Pr(1), one Pr(2), and one Se(1) atom. In the second O site, O(5) is bonded in a 3-coordinate geometry to one Pr(1), one Pr(2), and one Se(1) atom. In the third O site, O(1) is bonded in a 3-coordinate geometry to two equivalent Pr(2) and one Se(2) atom. In the fourth O site, O(2) is bonded in a distorted water-like geometry to one Pr(2) and one Se(2) atom. In the fifth O site, O(3) is bonded in a 4-coordinate geometry to one Pr(2), two equivalent Pr(1), and one Se(1) atom. There are three inequivalent F sites. In the first F site, F(1) is bonded in a trigonal non-coplanar geometry to one Pr(2) and two equivalent Pr(1) atoms. In the second F site, F(2) is bonded in a distorted trigonal planar geometry to one Pr(1) and two equivalent Pr(2) atoms. In the third F site, F(3) is bonded in a 4-coordinate geometry to one Pr(2) and three equivalent Pr(1) atoms.
Pr4Se3(O5F3)2 crystallizes in the monoclinic C2/c space group. There are two inequivalent Pr sites. In the first Pr site, Pr(1) is bonded in a 10-coordinate geometry to one O(4), one O(5), two equivalent O(3), one F(2), two equivalent F(1), and three equivalent F(3) atoms. The Pr(1)-O(4) bond length is 2.48 Å. The Pr(1)-O(5) bond length is 2.68 Å. There is one shorter (2.68 Å) and one longer (2.83 Å) Pr(1)-O(3) bond length. The Pr(1)-F(2) bond length is 2.53 Å. Both Pr(1)-F(1) bond lengths are 2.39 Å. There are a spread of Pr(1)-F(3) bond distances ranging from 2.45-2.64 Å. In the second Pr site, Pr(2) is bonded in a 10-coordinate geometry to one O(2), one O(3), one O(4), one O(5), two equivalent O(1), one F(1), one F(3), and two equivalent F(2) atoms. The Pr(2)-O(2) bond length is 2.71 Å. The Pr(2)-O(3) bond length is 2.53 Å. The Pr(2)-O(4) bond length is 2.53 Å. The Pr(2)-O(5) bond length is 2.44 Å. There is one shorter (2.58 Å) and one longer (2.76 Å) Pr(2)-O(1) bond length. The Pr(2)-F(1) bond length is 2.44 Å. The Pr(2)-F(3) bond length is 2.94 Å. There is one shorter (2.44 Å) and one longer (2.51 Å) Pr(2)-F(2) 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(3), one O(4), and one O(5) atom. The Se(1)-O(3) bond length is 1.75 Å. The Se(1)-O(4) bond length is 1.75 Å. The Se(1)-O(5) bond length is 1.71 Å. In the second Se site, Se(2) is bonded in a tetrahedral geometry to two equivalent O(1) and two equivalent O(2) atoms. Both Se(2)-O(1) bond lengths are 1.69 Å. Both Se(2)-O(2) bond lengths are 1.67 Å. There are five inequivalent O sites. In the first O site, O(4) is bonded in a distorted trigonal planar geometry to one Pr(1), one Pr(2), and one Se(1) atom. In the second O site, O(5) is bonded in a 3-coordinate geometry to one Pr(1), one Pr(2), and one Se(1) atom. In the third O site, O(1) is bonded in a 3-coordinate geometry to two equivalent Pr(2) and one Se(2) atom. In the fourth O site, O(2) is bonded in a distorted water-like geometry to one Pr(2) and one Se(2) atom. In the fifth O site, O(3) is bonded in a 4-coordinate geometry to one Pr(2), two equivalent Pr(1), and one Se(1) atom. There are three inequivalent F sites. In the first F site, F(1) is bonded in a trigonal non-coplanar geometry to one Pr(2) and two equivalent Pr(1) atoms. In the second F site, F(2) is bonded in a distorted trigonal planar geometry to one Pr(1) and two equivalent Pr(2) atoms. In the third F site, F(3) is bonded in a 4-coordinate geometry to one Pr(2) and three equivalent Pr(1) atoms.