Materials Data on Mg6CrC by Materials Project

Abstract

Mg6CrC crystallizes in the orthorhombic Amm2 space group. The structure is three-dimensional. there are four inequivalent Mg sites. In the first Mg site, Mg is bonded in a 2-coordinate geometry to eight Mg, two equivalent Cr, and one C atom. There are a spread of Mg–Mg bond distances ranging from 2.92–3.09 Å. There are one shorter (3.02 Å) and one longer (3.06 Å) Mg–Cr bond lengths. The Mg–C bond length is 2.95 Å. In the second Mg site, Mg is bonded in a 12-coordinate geometry to eight Mg, two equivalent Cr, and two equivalent C atoms. There are a spread of Mg–Mg bond distances ranging from 2.86–3.22 Å. Both Mg–Cr bond lengths are 2.93 Å. Both Mg–C bond lengths are 2.89 Å. In the third Mg site, Mg is bonded to ten Mg and two equivalent Cr atoms to form a mixture of distorted corner and face-sharing MgMg10Cr2 cuboctahedra. Both Mg–Mg bond lengths are 3.09 Å. Both Mg–Cr bond lengths are 2.87 Å. In the fourth Mg site, Mg is bonded in a distorted bent 120 degrees geometry to ten Mg and two equivalent C atoms. Both Mg–C bond lengths are 2.79 Å. Cr is bonded in a distorted q6 geometry to ten Mg atoms. C is bonded in a 2-coordinate geometry to eight Mg atoms.