Sr3Fe2O5Cu2S2 crystallizes in the tetragonal I4/mmm space group. There are two inequivalent Sr sites. In the first Sr site, Sr(1) is bonded to four equivalent O(2) and eight equivalent O(1) atoms to form SrO12 cuboctahedra that share corners with four equivalent Sr(1)O12 cuboctahedra, faces with four equivalent Sr(1)O12 cuboctahedra, and faces with eight equivalent Fe(1)O5 square pyramids. In the second Sr site, Sr(2) is bonded in a 4-coordinate geometry to four equivalent S(1) and four equivalent O(1) atoms. Fe(1) is bonded to one O(2) and four equivalent O(1) atoms to form FeO5 square pyramids that share corners with five equivalent Fe(1)O5 square pyramids and faces with four equivalent Sr(1)O12 cuboctahedra. Cu(1) is bonded to four equivalent S(1) atoms to form a mixture of edge and corner-sharing CuS4 tetrahedra. S(1) is bonded in a 8-coordinate geometry to four equivalent Sr(2) and four equivalent Cu(1) atoms. There are two inequivalent O sites. In the first O site, O(1) is bonded in a 6-coordinate geometry to two equivalent Sr(1), two equivalent Sr(2), and two equivalent Fe(1) atoms. In the second O site, O(2) is bonded to four equivalent Sr(1) and two equivalent Fe(1) atoms to form a mixture of distorted edge and corner-sharing OSr4Fe2 octahedra. The corner-sharing octahedra are not tilted.
Sr3Fe2O5Cu2S2 crystallizes in the tetragonal I4/mmm space group. There are two inequivalent Sr sites. In the first Sr site, Sr(1) is bonded to four equivalent O(2) and eight equivalent O(1) atoms to form SrO12 cuboctahedra that share corners with four equivalent Sr(1)O12 cuboctahedra, faces with four equivalent Sr(1)O12 cuboctahedra, and faces with eight equivalent Fe(1)O5 square pyramids. All Sr(1)-O(2) bond lengths are 2.80 Å. All Sr(1)-O(1) bond lengths are 2.97 Å. In the second Sr site, Sr(2) is bonded in a 4-coordinate geometry to four equivalent S(1) and four equivalent O(1) atoms. All Sr(2)-S(1) bond lengths are 3.17 Å. All Sr(2)-O(1) bond lengths are 2.54 Å. Fe(1) is bonded to one O(2) and four equivalent O(1) atoms to form FeO5 square pyramids that share corners with five equivalent Fe(1)O5 square pyramids and faces with four equivalent Sr(1)O12 cuboctahedra. The Fe(1)-O(2) bond length is 1.93 Å. All Fe(1)-O(1) bond lengths are 2.00 Å. Cu(1) is bonded to four equivalent S(1) atoms to form a mixture of edge and corner-sharing CuS4 tetrahedra. All Cu(1)-S(1) bond lengths are 2.42 Å. S(1) is bonded in a 8-coordinate geometry to four equivalent Sr(2) and four equivalent Cu(1) atoms. There are two inequivalent O sites. In the first O site, O(1) is bonded in a 6-coordinate geometry to two equivalent Sr(1), two equivalent Sr(2), and two equivalent Fe(1) atoms. In the second O site, O(2) is bonded to four equivalent Sr(1) and two equivalent Fe(1) atoms to form a mixture of distorted edge and corner-sharing OSr4Fe2 octahedra. The corner-sharing octahedra are not tilted.