Y2OsC2 crystallizes in the orthorhombic Pnma space group. There are two inequivalent Y sites. In the first Y site, Y(1) is bonded to two equivalent C(1) and three equivalent C(2) atoms to form a mixture of distorted corner and edge-sharing YC5 square pyramids. In the second Y site, Y(2) is bonded in a distorted rectangular see-saw-like geometry to two equivalent C(1) and two equivalent C(2) atoms. Os(1) is bonded in a distorted trigonal planar geometry to one C(2) and two equivalent C(1) atoms. There are two inequivalent C sites. In the first C site, C(1) is bonded to two equivalent Y(1), two equivalent Y(2), and two equivalent Os(1) atoms to form CY4Os2 octahedra that share corners with two equivalent C(1)Y4Os2 octahedra, corners with two equivalent C(2)Y5Os octahedra, edges with two equivalent C(1)Y4Os2 octahedra, and edges with five equivalent C(2)Y5Os octahedra. The corner-sharing octahedral tilt angles range from 10-40°. In the second C site, C(2) is bonded to two equivalent Y(2), three equivalent Y(1), and one Os(1) atom to form CY5Os octahedra that share corners with two equivalent C(1)Y4Os2 octahedra, corners with four equivalent C(2)Y5Os octahedra, edges with two equivalent C(2)Y5Os octahedra, and edges with five equivalent C(1)Y4Os2 octahedra. The corner-sharing octahedral tilt angles range from 2-40°.
Y2OsC2 crystallizes in the orthorhombic Pnma space group. There are two inequivalent Y sites. In the first Y site, Y(1) is bonded to two equivalent C(1) and three equivalent C(2) atoms to form a mixture of distorted corner and edge-sharing YC5 square pyramids. There is one shorter (2.47 Å) and one longer (2.58 Å) Y(1)-C(1) bond length. There is one shorter (2.54 Å) and two longer (2.57 Å) Y(1)-C(2) bond lengths. In the second Y site, Y(2) is bonded in a distorted rectangular see-saw-like geometry to two equivalent C(1) and two equivalent C(2) atoms. Both Y(2)-C(1) bond lengths are 2.58 Å. There is one shorter (2.52 Å) and one longer (2.61 Å) Y(2)-C(2) bond length. Os(1) is bonded in a distorted trigonal planar geometry to one C(2) and two equivalent C(1) atoms. The Os(1)-C(2) bond length is 1.94 Å. There is one shorter (1.94 Å) and one longer (1.99 Å) Os(1)-C(1) bond length. There are two inequivalent C sites. In the first C site, C(1) is bonded to two equivalent Y(1), two equivalent Y(2), and two equivalent Os(1) atoms to form CY4Os2 octahedra that share corners with two equivalent C(1)Y4Os2 octahedra, corners with two equivalent C(2)Y5Os octahedra, edges with two equivalent C(1)Y4Os2 octahedra, and edges with five equivalent C(2)Y5Os octahedra. The corner-sharing octahedral tilt angles range from 10-40°. In the second C site, C(2) is bonded to two equivalent Y(2), three equivalent Y(1), and one Os(1) atom to form CY5Os octahedra that share corners with two equivalent C(1)Y4Os2 octahedra, corners with four equivalent C(2)Y5Os octahedra, edges with two equivalent C(2)Y5Os octahedra, and edges with five equivalent C(1)Y4Os2 octahedra. The corner-sharing octahedral tilt angles range from 2-40°.