SrFe2Se2O crystallizes in the triclinic P1 space group. There are two inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a distorted water-like geometry to one Se(1), one Se(2), two equivalent Se(3), two equivalent Se(4), and two equivalent O(2) atoms. In the second Sr site, Sr(2) is bonded in a distorted water-like geometry to one Se(3), one Se(4), two equivalent Se(1), two equivalent Se(2), and two equivalent O(1) atoms. There are four inequivalent Fe sites. In the first Fe site, Fe(1) is bonded in a distorted single-bond geometry to one Se(2), two equivalent Se(3), and one O(1) atom. In the second Fe site, Fe(2) is bonded to one Se(4), two equivalent Se(1), and one O(2) atom to form a mixture of distorted edge and corner-sharing FeSe3O tetrahedra. In the third Fe site, Fe(3) is bonded to one Se(1), two equivalent Se(4), and one O(1) atom to form a mixture of distorted edge and corner-sharing FeSe3O tetrahedra. In the fourth Fe site, Fe(4) is bonded to one Se(3), two equivalent Se(2), and one O(2) atom to form distorted corner-sharing FeSe3O tetrahedra. There are four inequivalent Se sites. In the first Se site, Se(1) is bonded in a 6-coordinate geometry to one Sr(1), two equivalent Sr(2), one Fe(3), and two equivalent Fe(2) atoms. In the second Se site, Se(2) is bonded in a 6-coordinate geometry to one Sr(1), two equivalent Sr(2), one Fe(1), and two equivalent Fe(4) atoms. In the third Se site, Se(3) is bonded in a 6-coordinate geometry to one Sr(2), two equivalent Sr(1), one Fe(4), and two equivalent Fe(1) atoms. In the fourth Se site, Se(4) is bonded in a 6-coordinate geometry to one Sr(2), two equivalent Sr(1), one Fe(2), and two equivalent Fe(3) atoms. There are two inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Sr(2), one Fe(1), and one Fe(3) atom to form corner-sharing OSr2Fe2 tetrahedra. In the second O site, O(2) is bonded to two equivalent Sr(1), one Fe(2), and one Fe(4) atom to form corner-sharing OSr2Fe2 tetrahedra.
SrFe2Se2O crystallizes in the triclinic P1 space group. There are two inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a distorted water-like geometry to one Se(1), one Se(2), two equivalent Se(3), two equivalent Se(4), and two equivalent O(2) atoms. The Sr(1)-Se(1) bond length is 3.46 Å. The Sr(1)-Se(2) bond length is 3.42 Å. There is one shorter (3.31 Å) and one longer (3.34 Å) Sr(1)-Se(3) bond length. There is one shorter (3.32 Å) and one longer (3.34 Å) Sr(1)-Se(4) bond length. There is one shorter (2.51 Å) and one longer (2.52 Å) Sr(1)-O(2) bond length. In the second Sr site, Sr(2) is bonded in a distorted water-like geometry to one Se(3), one Se(4), two equivalent Se(1), two equivalent Se(2), and two equivalent O(1) atoms. The Sr(2)-Se(3) bond length is 3.44 Å. The Sr(2)-Se(4) bond length is 3.45 Å. There is one shorter (3.32 Å) and one longer (3.33 Å) Sr(2)-Se(1) bond length. There is one shorter (3.32 Å) and one longer (3.33 Å) Sr(2)-Se(2) bond length. There is one shorter (2.51 Å) and one longer (2.53 Å) Sr(2)-O(1) bond length. There are four inequivalent Fe sites. In the first Fe site, Fe(1) is bonded in a distorted single-bond geometry to one Se(2), two equivalent Se(3), and one O(1) atom. The Fe(1)-Se(2) bond length is 2.55 Å. There is one shorter (2.59 Å) and one longer (2.60 Å) Fe(1)-Se(3) bond length. The Fe(1)-O(1) bond length is 1.93 Å. In the second Fe site, Fe(2) is bonded to one Se(4), two equivalent Se(1), and one O(2) atom to form a mixture of distorted edge and corner-sharing FeSe3O tetrahedra. The Fe(2)-Se(4) bond length is 2.55 Å. There is one shorter (2.59 Å) and one longer (2.60 Å) Fe(2)-Se(1) bond length. The Fe(2)-O(2) bond length is 1.93 Å. In the third Fe site, Fe(3) is bonded to one Se(1), two equivalent Se(4), and one O(1) atom to form a mixture of distorted edge and corner-sharing FeSe3O tetrahedra. The Fe(3)-Se(1) bond length is 2.56 Å. There is one shorter (2.57 Å) and one longer (2.61 Å) Fe(3)-Se(4) bond length. The Fe(3)-O(1) bond length is 1.93 Å. In the fourth Fe site, Fe(4) is bonded to one Se(3), two equivalent Se(2), and one O(2) atom to form distorted corner-sharing FeSe3O tetrahedra. The Fe(4)-Se(3) bond length is 2.55 Å. There is one shorter (2.58 Å) and one longer (2.61 Å) Fe(4)-Se(2) bond length. The Fe(4)-O(2) bond length is 1.93 Å. There are four inequivalent Se sites. In the first Se site, Se(1) is bonded in a 6-coordinate geometry to one Sr(1), two equivalent Sr(2), one Fe(3), and two equivalent Fe(2) atoms. In the second Se site, Se(2) is bonded in a 6-coordinate geometry to one Sr(1), two equivalent Sr(2), one Fe(1), and two equivalent Fe(4) atoms. In the third Se site, Se(3) is bonded in a 6-coordinate geometry to one Sr(2), two equivalent Sr(1), one Fe(4), and two equivalent Fe(1) atoms. In the fourth Se site, Se(4) is bonded in a 6-coordinate geometry to one Sr(2), two equivalent Sr(1), one Fe(2), and two equivalent Fe(3) atoms. There are two inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Sr(2), one Fe(1), and one Fe(3) atom to form corner-sharing OSr2Fe2 tetrahedra. In the second O site, O(2) is bonded to two equivalent Sr(1), one Fe(2), and one Fe(4) atom to form corner-sharing OSr2Fe2 tetrahedra.