Materials Data on SrMg6C by Materials Project
SrMg6C crystallizes in the orthorhombic Amm2 space group. The structure is three-dimensional. Sr is bonded in a 6-coordinate geometry to ten Mg atoms. There are a spread of Sr–Mg bond distances ranging from 3.24–4.00 Å. There are four inequivalent Mg sites. In the first Mg site, Mg is bonded in a single-bond geometry to four Mg and one C atom. There are two shorter (2.96 Å) and two longer (3.32 Å) Mg–Mg bond lengths. The Mg–C bond length is 2.29 Å. In the second Mg site, Mg is bonded in a distorted bent 120 degrees geometry to two equivalent Sr, one Mg, and two equivalent C atoms. The Mg–Mg bond length is 3.56 Å. Both Mg–C bond lengths are 2.63 Å. In the third Mg site, Mg is bonded in a 2-coordinate geometry to two equivalent Sr and six Mg atoms. Both Mg–Mg bond lengths are 3.00 Å. In the fourth Mg site, Mg is bonded in a 2-coordinate geometry to four equivalent Sr and eight Mg atoms. C is bonded in a 6-coordinate geometry to six Mg atoms.