Sr4FeMoO8 is (La,Ba)CuO4-derived structured and crystallizes in the orthorhombic Cmmm space group. There are two inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a 9-coordinate geometry to two equivalent O(2), three equivalent O(1), and four equivalent O(3) atoms. In the second Sr site, Sr(2) is bonded in a 9-coordinate geometry to two equivalent O(1), three equivalent O(2), and four equivalent O(3) atoms. Mo(1) is bonded to two equivalent O(2) and four equivalent O(3) atoms to form MoO6 octahedra that share corners with four equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles are 1°. Fe(1) is bonded to two equivalent O(1) and four equivalent O(3) atoms to form FeO6 octahedra that share corners with four equivalent Mo(1)O6 octahedra. The corner-sharing octahedral tilt angles are 1°. There are three inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Sr(2), three equivalent Sr(1), and one Fe(1) atom to form distorted OSr5Fe octahedra that share corners with five equivalent O(1)Sr5Fe octahedra, corners with twelve equivalent O(3)Sr4FeMo octahedra, edges with two equivalent O(1)Sr5Fe octahedra, edges with six equivalent O(2)Sr5Mo octahedra, and faces with four equivalent O(3)Sr4FeMo octahedra. The corner-sharing octahedral tilt angles range from 0-57°. In the second O site, O(2) is bonded to two equivalent Sr(1), three equivalent Sr(2), and one Mo(1) atom to form OSr5Mo octahedra that share corners with five equivalent O(2)Sr5Mo octahedra, corners with twelve equivalent O(3)Sr4FeMo octahedra, edges with two equivalent O(2)Sr5Mo octahedra, edges with six equivalent O(1)Sr5Fe octahedra, and faces with four equivalent O(3)Sr4FeMo octahedra. The corner-sharing octahedral tilt angles range from 0-56°. In the third O site, O(3) is bonded to two equivalent Sr(1), two equivalent Sr(2), one Mo(1), and one Fe(1) atom to form distorted OSr4FeMo octahedra that share corners with two equivalent O(3)Sr4FeMo octahedra, corners with six equivalent O(1)Sr5Fe octahedra, corners with six equivalent O(2)Sr5Mo octahedra, edges with two equivalent O(3)Sr4FeMo octahedra, faces with two equivalent O(1)Sr5Fe octahedra, faces with two equivalent O(2)Sr5Mo octahedra, and faces with four equivalent O(3)Sr4FeMo octahedra. The corner-sharing octahedral tilt angles range from 0-57°.
Sr4FeMoO8 is (La,Ba)CuO4-derived structured and crystallizes in the orthorhombic Cmmm space group. There are two inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a 9-coordinate geometry to two equivalent O(2), three equivalent O(1), and four equivalent O(3) atoms. Both Sr(1)-O(2) bond lengths are 2.84 Å. There is one shorter (2.44 Å) and two longer (2.80 Å) Sr(1)-O(1) bond lengths. All Sr(1)-O(3) bond lengths are 2.74 Å. In the second Sr site, Sr(2) is bonded in a 9-coordinate geometry to two equivalent O(1), three equivalent O(2), and four equivalent O(3) atoms. Both Sr(2)-O(1) bond lengths are 2.84 Å. There is one shorter (2.47 Å) and two longer (2.80 Å) Sr(2)-O(2) bond lengths. All Sr(2)-O(3) bond lengths are 2.74 Å. Mo(1) is bonded to two equivalent O(2) and four equivalent O(3) atoms to form MoO6 octahedra that share corners with four equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles are 1°. Both Mo(1)-O(2) bond lengths are 2.07 Å. All Mo(1)-O(3) bond lengths are 1.97 Å. Fe(1) is bonded to two equivalent O(1) and four equivalent O(3) atoms to form FeO6 octahedra that share corners with four equivalent Mo(1)O6 octahedra. The corner-sharing octahedral tilt angles are 1°. Both Fe(1)-O(1) bond lengths are 2.07 Å. All Fe(1)-O(3) bond lengths are 2.01 Å. There are three inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Sr(2), three equivalent Sr(1), and one Fe(1) atom to form distorted OSr5Fe octahedra that share corners with five equivalent O(1)Sr5Fe octahedra, corners with twelve equivalent O(3)Sr4FeMo octahedra, edges with two equivalent O(1)Sr5Fe octahedra, edges with six equivalent O(2)Sr5Mo octahedra, and faces with four equivalent O(3)Sr4FeMo octahedra. The corner-sharing octahedral tilt angles range from 0-57°. In the second O site, O(2) is bonded to two equivalent Sr(1), three equivalent Sr(2), and one Mo(1) atom to form OSr5Mo octahedra that share corners with five equivalent O(2)Sr5Mo octahedra, corners with twelve equivalent O(3)Sr4FeMo octahedra, edges with two equivalent O(2)Sr5Mo octahedra, edges with six equivalent O(1)Sr5Fe octahedra, and faces with four equivalent O(3)Sr4FeMo octahedra. The corner-sharing octahedral tilt angles range from 0-56°. In the third O site, O(3) is bonded to two equivalent Sr(1), two equivalent Sr(2), one Mo(1), and one Fe(1) atom to form distorted OSr4FeMo octahedra that share corners with two equivalent O(3)Sr4FeMo octahedra, corners with six equivalent O(1)Sr5Fe octahedra, corners with six equivalent O(2)Sr5Mo octahedra, edges with two equivalent O(3)Sr4FeMo octahedra, faces with two equivalent O(1)Sr5Fe octahedra, faces with two equivalent O(2)Sr5Mo octahedra, and faces with four equivalent O(3)Sr4FeMo octahedra. The corner-sharing octahedral tilt angles range from 0-57°.