Materials Data on SrMg6B by Materials Project
SrMg6B crystallizes in the orthorhombic Amm2 space group. The structure is three-dimensional. Sr is bonded in a 8-coordinate geometry to ten Mg and two equivalent B atoms. There are a spread of Sr–Mg bond distances ranging from 3.28–3.99 Å. Both Sr–B bond lengths are 3.38 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 B atom. There are two shorter (2.97 Å) and two longer (3.45 Å) Mg–Mg bond lengths. The Mg–B bond length is 2.44 Å. In the second Mg site, Mg is bonded in a 2-coordinate geometry to two equivalent Sr, two Mg, and two equivalent B atoms. There are one shorter (3.29 Å) and one longer (3.32 Å) Mg–Mg bond lengths. Both Mg–B bond lengths are 2.70 Å. In the third Mg site, Mg is bonded in a 2-coordinate geometry to two equivalent Sr and eight Mg atoms. Both Mg–Mg bond lengths are 3.11 Å. In the fourth Mg site, Mg is bonded in a 12-coordinate geometry to four equivalent Sr and eight Mg atoms. B is bonded in a 6-coordinate geometry to two equivalent Sr and six Mg atoms.