Materials Data on Mg2Cu2O5 by Materials Project
Mg2Cu2O5 crystallizes in the orthorhombic Pbam space group. The structure is three-dimensional. Mg2+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Mg–O bond distances ranging from 2.09–2.45 Å. Cu3+ is bonded to five O2- atoms to form corner-sharing CuO5 square pyramids. There are a spread of Cu–O bond distances ranging from 1.90–2.04 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded to four equivalent Mg2+ and two equivalent Cu3+ atoms to form distorted OMg4Cu2 octahedra that share corners with eight equivalent OMg2Cu2 tetrahedra, corners with four equivalent OMg3Cu2 trigonal bipyramids, edges with two equivalent OMg4Cu2 octahedra, edges with two equivalent OMg2Cu2 tetrahedra, and faces with four equivalent OMg3Cu2 trigonal bipyramids. In the second O2- site, O2- is bonded to two equivalent Mg2+ and two equivalent Cu3+ atoms to form OMg2Cu2 tetrahedra that share corners with four equivalent OMg4Cu2 octahedra, corners with four equivalent OMg2Cu2 tetrahedra, corners with six equivalent OMg3Cu2 trigonal bipyramids, an edgeedge with one OMg4Cu2 octahedra, and edges with two equivalent OMg3Cu2 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 12–59°. In the third O2- site, O2- is bonded to three equivalent Mg2+ and two equivalent Cu3+ atoms to form distorted OMg3Cu2 trigonal bipyramids that share corners with two equivalent OMg4Cu2 octahedra, corners with six equivalent OMg2Cu2 tetrahedra, corners with four equivalent OMg3Cu2 trigonal bipyramids, edges with two equivalent OMg2Cu2 tetrahedra, edges with two equivalent OMg3Cu2 trigonal bipyramids, and faces with two equivalent OMg4Cu2 octahedra. The corner-sharing octahedral tilt angles are 64°.