Sr2FeReO6 crystallizes in the triclinic P-1 space group. There are four inequivalent Sr sites. In the first Sr site, Sr(1) is bonded to one O(1), one O(10), one O(11), one O(4), one O(5), one O(8), two equivalent O(12), two equivalent O(2), and two equivalent O(6) atoms to form distorted SrO12 cuboctahedra that share corners with three equivalent Sr(3)O12 cuboctahedra, corners with three equivalent Sr(4)O12 cuboctahedra, corners with six equivalent Sr(1)O12 cuboctahedra, faces with three equivalent Sr(2)O12 cuboctahedra, faces with three equivalent Sr(4)O12 cuboctahedra,  a faceface with one Re(3)O6 octahedra,  a faceface with one Fe(1)O6 octahedra, faces with three equivalent Re(1)O6 octahedra, and faces with three equivalent Fe(2)O6 octahedra. In the second Sr site, Sr(2) is bonded to one O(12), one O(2), one O(3), one O(6), one O(7), one O(9), two equivalent O(1), two equivalent O(11), and two equivalent O(5) atoms to form distorted SrO12 cuboctahedra that share corners with three equivalent Sr(3)O12 cuboctahedra, corners with three equivalent Sr(4)O12 cuboctahedra, corners with six equivalent Sr(2)O12 cuboctahedra, faces with three equivalent Sr(1)O12 cuboctahedra, faces with three equivalent Sr(3)O12 cuboctahedra,  a faceface with one Re(2)O6 octahedra,  a faceface with one Fe(2)O6 octahedra, faces with three equivalent Re(1)O6 octahedra, and faces with three equivalent Fe(1)O6 octahedra. In the third Sr site, Sr(3) is bonded to one O(1), one O(11), one O(5), three equivalent O(3), three equivalent O(7), and three equivalent O(9) atoms to form distorted SrO12 cuboctahedra that share corners with three equivalent Sr(1)O12 cuboctahedra, corners with three equivalent Sr(2)O12 cuboctahedra, corners with six equivalent Sr(3)O12 cuboctahedra, faces with three equivalent Sr(2)O12 cuboctahedra, faces with three equivalent Sr(3)O12 cuboctahedra,  a faceface with one Re(1)O6 octahedra, faces with three equivalent Re(2)O6 octahedra, and faces with four equivalent Fe(1)O6 octahedra. In the fourth Sr site, Sr(4) is bonded to one O(12), one O(2), one O(6), three equivalent O(10), three equivalent O(4), and three equivalent O(8) atoms to form distorted SrO12 cuboctahedra that share corners with three equivalent Sr(1)O12 cuboctahedra, corners with three equivalent Sr(2)O12 cuboctahedra, corners with six equivalent Sr(4)O12 cuboctahedra, faces with three equivalent Sr(1)O12 cuboctahedra, faces with three equivalent Sr(4)O12 cuboctahedra,  a faceface with one Re(1)O6 octahedra, faces with three equivalent Re(3)O6 octahedra, and faces with four equivalent Fe(2)O6 octahedra. There are three inequivalent Re sites. In the first Re site, Re(1) is bonded to one O(1), one O(11), one O(12), one O(2), one O(5), and one O(6) atom to form ReO6 octahedra that share corners with three equivalent Fe(1)O6 octahedra, corners with three equivalent Fe(2)O6 octahedra,  a faceface with one Sr(3)O12 cuboctahedra,  a faceface with one Sr(4)O12 cuboctahedra, faces with three equivalent Sr(1)O12 cuboctahedra, and faces with three equivalent Sr(2)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-16°. In the second Re site, Re(2) is bonded to two equivalent O(3), two equivalent O(7), and two equivalent O(9) atoms to form ReO6 octahedra that share corners with six equivalent Fe(1)O6 octahedra, faces with two equivalent Sr(2)O12 cuboctahedra, and faces with six equivalent Sr(3)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-17°. In the third Re site, Re(3) is bonded to two equivalent O(10), two equivalent O(4), and two equivalent O(8) atoms to form ReO6 octahedra that share corners with six equivalent Fe(2)O6 octahedra, faces with two equivalent Sr(1)O12 cuboctahedra, and faces with six equivalent Sr(4)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 2-18°. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(1), one O(11), one O(3), one O(5), one O(7), and one O(9) atom to form FeO6 octahedra that share corners with three equivalent Re(1)O6 octahedra, corners with three equivalent Re(2)O6 octahedra,  a faceface with one Sr(1)O12 cuboctahedra, faces with three equivalent Sr(2)O12 cuboctahedra, and faces with four equivalent Sr(3)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-17°. In the second Fe site, Fe(2) is bonded to one O(10), one O(12), one O(2), one O(4), one O(6), and one O(8) atom to form FeO6 octahedra that share corners with three equivalent Re(1)O6 octahedra, corners with three equivalent Re(3)O6 octahedra,  a faceface with one Sr(2)O12 cuboctahedra, faces with three equivalent Sr(1)O12 cuboctahedra, and faces with four equivalent Sr(4)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 1-18°. There are twelve inequivalent O sites. In the first O site, O(1) is bonded to one Sr(1), one Sr(3), two equivalent Sr(2), one Re(1), and one Fe(1) atom to form a mixture of distorted edge and corner-sharing OSr4FeRe octahedra. The corner-sharing octahedral tilt angles range from 1-2°. In the second O site, O(2) is bonded to one Sr(2), one Sr(4), two equivalent Sr(1), one Re(1), and one Fe(2) atom to form a mixture of distorted edge and corner-sharing OSr4FeRe octahedra. The corner-sharing octahedral tilt angles range from 1-3°. In the third O site, O(3) is bonded to one Sr(2), three equivalent Sr(3), one Re(2), and one Fe(1) atom to form a mixture of distorted edge and corner-sharing OSr4FeRe octahedra. The corner-sharing octahedral tilt angles range from 0-2°. In the fourth O site, O(4) is bonded to one Sr(1), three equivalent Sr(4), one Re(3), and one Fe(2) atom to form a mixture of distorted edge and corner-sharing OSr4FeRe octahedra. The corner-sharing octahedral tilt angles range from 0-3°. In the fifth O site, O(5) is bonded in a 4-coordinate geometry to one Sr(1), one Sr(3), two equivalent Sr(2), one Re(1), and one Fe(1) atom. In the sixth O site, O(6) is bonded in a 4-coordinate geometry to one Sr(2), one Sr(4), two equivalent Sr(1), one Re(1), and one Fe(2) atom. In the seventh O site, O(7) is bonded in a 4-coordinate geometry to one Sr(2), three equivalent Sr(3), one Re(2), and one Fe(1) atom. In the eighth O site, O(8) is bonded in a 4-coordinate geometry to one Sr(1), three equivalent Sr(4), one Re(3), and one Fe(2) atom. In the ninth O site, O(9) is bonded in a 4-coordinate geometry to one Sr(2), three equivalent Sr(3), one Re(2), and one Fe(1) atom. In the tenth O site, O(10) is bonded in a 4-coordinate geometry to one Sr(1), three equivalent Sr(4), one Re(3), and one Fe(2) atom. In the eleventh O site, O(11) is bonded in a 4-coordinate geometry to one Sr(1), one Sr(3), two equivalent Sr(2), one Re(1), and one Fe(1) atom. In the twelfth O site, O(12) is bonded in a 4-coordinate geometry to one Sr(2), one Sr(4), two equivalent Sr(1), one Re(1), and one Fe(2) atom.
Sr2FeReO6 crystallizes in the triclinic P-1 space group. There are four inequivalent Sr sites. In the first Sr site, Sr(1) is bonded to one O(1), one O(10), one O(11), one O(4), one O(5), one O(8), two equivalent O(12), two equivalent O(2), and two equivalent O(6) atoms to form distorted SrO12 cuboctahedra that share corners with three equivalent Sr(3)O12 cuboctahedra, corners with three equivalent Sr(4)O12 cuboctahedra, corners with six equivalent Sr(1)O12 cuboctahedra, faces with three equivalent Sr(2)O12 cuboctahedra, faces with three equivalent Sr(4)O12 cuboctahedra,  a faceface with one Re(3)O6 octahedra,  a faceface with one Fe(1)O6 octahedra, faces with three equivalent Re(1)O6 octahedra, and faces with three equivalent Fe(2)O6 octahedra. The Sr(1)-O(1) bond length is 2.81 Å. The Sr(1)-O(10) bond length is 3.02 Å. The Sr(1)-O(11) bond length is 2.64 Å. The Sr(1)-O(4) bond length is 2.80 Å. The Sr(1)-O(5) bond length is 3.03 Å. The Sr(1)-O(8) bond length is 2.62 Å. There is one shorter (2.64 Å) and one longer (3.02 Å) Sr(1)-O(12) bond length. There is one shorter (2.80 Å) and one longer (2.81 Å) Sr(1)-O(2) bond length. There is one shorter (2.63 Å) and one longer (3.02 Å) Sr(1)-O(6) bond length. In the second Sr site, Sr(2) is bonded to one O(12), one O(2), one O(3), one O(6), one O(7), one O(9), two equivalent O(1), two equivalent O(11), and two equivalent O(5) atoms to form distorted SrO12 cuboctahedra that share corners with three equivalent Sr(3)O12 cuboctahedra, corners with three equivalent Sr(4)O12 cuboctahedra, corners with six equivalent Sr(2)O12 cuboctahedra, faces with three equivalent Sr(1)O12 cuboctahedra, faces with three equivalent Sr(3)O12 cuboctahedra,  a faceface with one Re(2)O6 octahedra,  a faceface with one Fe(2)O6 octahedra, faces with three equivalent Re(1)O6 octahedra, and faces with three equivalent Fe(1)O6 octahedra. The Sr(2)-O(12) bond length is 2.62 Å. The Sr(2)-O(2) bond length is 2.78 Å. The Sr(2)-O(3) bond length is 2.82 Å. The Sr(2)-O(6) bond length is 3.00 Å. The Sr(2)-O(7) bond length is 2.65 Å. The Sr(2)-O(9) bond length is 3.04 Å. There is one shorter (2.80 Å) and one longer (2.81 Å) Sr(2)-O(1) bond length. There is one shorter (2.63 Å) and one longer (3.02 Å) Sr(2)-O(11) bond length. There is one shorter (2.63 Å) and one longer (3.03 Å) Sr(2)-O(5) bond length. In the third Sr site, Sr(3) is bonded to one O(1), one O(11), one O(5), three equivalent O(3), three equivalent O(7), and three equivalent O(9) atoms to form distorted SrO12 cuboctahedra that share corners with three equivalent Sr(1)O12 cuboctahedra, corners with three equivalent Sr(2)O12 cuboctahedra, corners with six equivalent Sr(3)O12 cuboctahedra, faces with three equivalent Sr(2)O12 cuboctahedra, faces with three equivalent Sr(3)O12 cuboctahedra,  a faceface with one Re(1)O6 octahedra, faces with three equivalent Re(2)O6 octahedra, and faces with four equivalent Fe(1)O6 octahedra. The Sr(3)-O(1) bond length is 2.81 Å. The Sr(3)-O(11) bond length is 3.02 Å. The Sr(3)-O(5) bond length is 2.64 Å. All Sr(3)-O(3) bond lengths are 2.80 Å. There are a spread of Sr(3)-O(7) bond distances ranging from 2.63-3.03 Å. There are two shorter (2.63 Å) and one longer (3.03 Å) Sr(3)-O(9) bond length. In the fourth Sr site, Sr(4) is bonded to one O(12), one O(2), one O(6), three equivalent O(10), three equivalent O(4), and three equivalent O(8) atoms to form distorted SrO12 cuboctahedra that share corners with three equivalent Sr(1)O12 cuboctahedra, corners with three equivalent Sr(2)O12 cuboctahedra, corners with six equivalent Sr(4)O12 cuboctahedra, faces with three equivalent Sr(1)O12 cuboctahedra, faces with three equivalent Sr(4)O12 cuboctahedra,  a faceface with one Re(1)O6 octahedra, faces with three equivalent Re(3)O6 octahedra, and faces with four equivalent Fe(2)O6 octahedra. The Sr(4)-O(12) bond length is 3.00 Å. The Sr(4)-O(2) bond length is 2.79 Å. The Sr(4)-O(6) bond length is 2.62 Å. There are a spread of Sr(4)-O(10) bond distances ranging from 2.63-3.03 Å. There are a spread of Sr(4)-O(4) bond distances ranging from 2.80-2.83 Å. There are a spread of Sr(4)-O(8) bond distances ranging from 2.63-3.05 Å. There are three inequivalent Re sites. In the first Re site, Re(1) is bonded to one O(1), one O(11), one O(12), one O(2), one O(5), and one O(6) atom to form ReO6 octahedra that share corners with three equivalent Fe(1)O6 octahedra, corners with three equivalent Fe(2)O6 octahedra,  a faceface with one Sr(3)O12 cuboctahedra,  a faceface with one Sr(4)O12 cuboctahedra, faces with three equivalent Sr(1)O12 cuboctahedra, and faces with three equivalent Sr(2)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-16°. The Re(1)-O(1) bond length is 1.96 Å. The Re(1)-O(11) bond length is 1.96 Å. The Re(1)-O(12) bond length is 1.97 Å. The Re(1)-O(2) bond length is 1.98 Å. The Re(1)-O(5) bond length is 1.96 Å. The Re(1)-O(6) bond length is 1.97 Å. In the second Re site, Re(2) is bonded to two equivalent O(3), two equivalent O(7), and two equivalent O(9) atoms to form ReO6 octahedra that share corners with six equivalent Fe(1)O6 octahedra, faces with two equivalent Sr(2)O12 cuboctahedra, and faces with six equivalent Sr(3)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-17°. Both Re(2)-O(3) bond lengths are 1.96 Å. Both Re(2)-O(7) bond lengths are 1.96 Å. Both Re(2)-O(9) bond lengths are 1.96 Å. In the third Re site, Re(3) is bonded to two equivalent O(10), two equivalent O(4), and two equivalent O(8) atoms to form ReO6 octahedra that share corners with six equivalent Fe(2)O6 octahedra, faces with two equivalent Sr(1)O12 cuboctahedra, and faces with six equivalent Sr(4)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 2-18°. Both Re(3)-O(10) bond lengths are 1.97 Å. Both Re(3)-O(4) bond lengths are 1.97 Å. Both Re(3)-O(8) bond lengths are 1.97 Å. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(1), one O(11), one O(3), one O(5), one O(7), and one O(9) atom to form FeO6 octahedra that share corners with three equivalent Re(1)O6 octahedra, corners with three equivalent Re(2)O6 octahedra,  a faceface with one Sr(1)O12 cuboctahedra, faces with three equivalent Sr(2)O12 cuboctahedra, and faces with four equivalent Sr(3)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-17°. The Fe(1)-O(1) bond length is 2.04 Å. The Fe(1)-O(11) bond length is 2.03 Å. The Fe(1)-O(3) bond length is 2.06 Å. The Fe(1)-O(5) bond length is 2.03 Å. The Fe(1)-O(7) bond length is 2.05 Å. The Fe(1)-O(9) bond length is 2.05 Å. In the second Fe site, Fe(2) is bonded to one O(10), one O(12), one O(2), one O(4), one O(6), and one O(8) atom to form FeO6 octahedra that share corners with three equivalent Re(1)O6 octahedra, corners with three equivalent Re(3)O6 octahedra,  a faceface with one Sr(2)O12 cuboctahedra, faces with three equivalent Sr(1)O12 cuboctahedra, and faces with four equivalent Sr(4)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 1-18°. The Fe(2)-O(10) bond length is 2.01 Å. The Fe(2)-O(12) bond length is 2.07 Å. The Fe(2)-O(2) bond length is 2.08 Å. The Fe(2)-O(4) bond length is 2.01 Å. The Fe(2)-O(6) bond length is 2.07 Å. The Fe(2)-O(8) bond length is 2.00 Å. There are twelve inequivalent O sites. In the first O site, O(1) is bonded to one Sr(1), one Sr(3), two equivalent Sr(2), one Re(1), and one Fe(1) atom to form a mixture of distorted edge and corner-sharing OSr4FeRe octahedra. The corner-sharing octahedral tilt angles range from 1-2°. In the second O site, O(2) is bonded to one Sr(2), one Sr(4), two equivalent Sr(1), one Re(1), and one Fe(2) atom to form a mixture of distorted edge and corner-sharing OSr4FeRe octahedra. The corner-sharing octahedral tilt angles range from 1-3°. In the third O site, O(3) is bonded to one Sr(2), three equivalent Sr(3), one Re(2), and one Fe(1) atom to form a mixture of distorted edge and corner-sharing OSr4FeRe octahedra. The corner-sharing octahedral tilt angles range from 0-2°. In the fourth O site, O(4) is bonded to one Sr(1), three equivalent Sr(4), one Re(3), and one Fe(2) atom to form a mixture of distorted edge and corner-sharing OSr4FeRe octahedra. The corner-sharing octahedral tilt angles range from 0-3°. In the fifth O site, O(5) is bonded in a 4-coordinate geometry to one Sr(1), one Sr(3), two equivalent Sr(2), one Re(1), and one Fe(1) atom. In the sixth O site, O(6) is bonded in a 4-coordinate geometry to one Sr(2), one Sr(4), two equivalent Sr(1), one Re(1), and one Fe(2) atom. In the seventh O site, O(7) is bonded in a 4-coordinate geometry to one Sr(2), three equivalent Sr(3), one Re(2), and one Fe(1) atom. In the eighth O site, O(8) is bonded in a 4-coordinate geometry to one Sr(1), three equivalent Sr(4), one Re(3), and one Fe(2) atom. In the ninth O site, O(9) is bonded in a 4-coordinate geometry to one Sr(2), three equivalent Sr(3), one Re(2), and one Fe(1) atom. In the tenth O site, O(10) is bonded in a 4-coordinate geometry to one Sr(1), three equivalent Sr(4), one Re(3), and one Fe(2) atom. In the eleventh O site, O(11) is bonded in a 4-coordinate geometry to one Sr(1), one Sr(3), two equivalent Sr(2), one Re(1), and one Fe(1) atom. In the twelfth O site, O(12) is bonded in a 4-coordinate geometry to one Sr(2), one Sr(4), two equivalent Sr(1), one Re(1), and one Fe(2) atom.