Sr₂RuO₄

Sr2RuO4 is (La,Ba)CuO4 structured and crystallizes in the tetragonal I4/mmm space group. Sr(1) is bonded in a 9-coordinate geometry to four equivalent O(2) and five equivalent O(1) atoms. All Sr(1)–O(2) bond lengths are 2.69 Å. There is one shorter (2.44 Å) and four longer (2.77 Å) Sr(1)–O(1) bond lengths. Ru(1) is bonded to two equivalent O(1) and four equivalent O(2) atoms to form corner-sharing RuO6 octahedra. The corner-sharing octahedra are not tilted. Both Ru(1)–O(1) bond lengths are 2.05 Å. All Ru(1)–O(2) bond lengths are 1.95 Å. There are two inequivalent O sites. In the first O site, O(2) is bonded to four equivalent Sr(1) and two equivalent Ru(1) atoms to form OSr4Ru2 octahedra that share corners with two equivalent O(2)Sr4Ru2 octahedra, corners with twelve equivalent O(1)Sr5Ru octahedra, edges with two equivalent O(2)Sr4Ru2 octahedra, faces with four equivalent O(2)Sr4Ru2 octahedra, and faces with four equivalent O(1)Sr5Ru octahedra. The corner-sharing octahedral tilt angles range from 0–56°. In the second O site, O(1) is bonded to five equivalent Sr(1) and one Ru(1) atom to form OSr5Ru octahedra that share corners with five equivalent O(1)Sr5Ru octahedra, corners with twelve equivalent O(2)Sr4Ru2 octahedra, edges with eight equivalent O(1)Sr5Ru octahedra, and faces with four equivalent O(2)Sr4Ru2 octahedra. The corner-sharing octahedral tilt angles range from 0–56°.