Materials Data on La4CuO8 by Materials Project
La4CuO8 crystallizes in the orthorhombic Cmmm space group. The structure is three-dimensional. there are two inequivalent La sites. In the first La site, La is bonded in a 9-coordinate geometry to nine O atoms. There are a spread of La–O bond distances ranging from 2.41–2.72 Å. In the second La site, La is bonded in a 9-coordinate geometry to nine O atoms. There are a spread of La–O bond distances ranging from 2.32–2.72 Å. Cu is bonded in an octahedral geometry to six O atoms. There are four shorter (1.83 Å) and two longer (2.37 Å) Cu–O bond lengths. There are three inequivalent O sites. In the first O site, O is bonded to five La and one Cu atom to form distorted OLa5Cu octahedra that share corners with five equivalent OLa5Cu octahedra, corners with twelve equivalent OLa4Cu square pyramids, edges with two equivalent OLa5Cu octahedra, edges with six equivalent OLa5 trigonal bipyramids, and faces with four equivalent OLa4Cu square pyramids. The corner-sharing octahedra tilt angles range from 0–26°. In the second O site, O is bonded to four La and one Cu atom to form distorted OLa4Cu square pyramids that share corners with six equivalent OLa5Cu octahedra, a cornercorner with one OLa4Cu square pyramid, corners with six equivalent OLa5 trigonal bipyramids, edges with four equivalent OLa4Cu square pyramids, edges with two equivalent OLa5 trigonal bipyramids, faces with two equivalent OLa5Cu octahedra, and faces with two equivalent OLa4Cu square pyramids. The corner-sharing octahedra tilt angles range from 47–49°. In the third O site, O is bonded to five La atoms to form distorted OLa5 trigonal bipyramids that share corners with twelve equivalent OLa4Cu square pyramids, corners with four equivalent OLa5 trigonal bipyramids, edges with six equivalent OLa5Cu octahedra, edges with four equivalent OLa4Cu square pyramids, and edges with two equivalent OLa5 trigonal bipyramids.