Materials Data on SrMg4 by Materials Project
SrMg4 crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. there are two inequivalent Sr sites. In the first Sr site, Sr is bonded in a 12-coordinate geometry to twelve Mg atoms. There are a spread of Sr–Mg bond distances ranging from 3.61–3.79 Å. In the second Sr site, Sr is bonded in a 10-coordinate geometry to fourteen Mg atoms. There are a spread of Sr–Mg bond distances ranging from 3.69–3.87 Å. There are nine inequivalent Mg sites. In the first Mg site, Mg is bonded in a 12-coordinate geometry to three equivalent Sr and nine Mg atoms. There are a spread of Mg–Mg bond distances ranging from 3.28–3.47 Å. In the second Mg site, Mg is bonded to four equivalent Sr and eight Mg atoms to form a mixture of corner and face-sharing MgSr4Mg8 cuboctahedra. There are four shorter (3.04 Å) and two longer (3.32 Å) Mg–Mg bond lengths. In the third Mg site, Mg is bonded to two equivalent Sr and ten Mg atoms to form a mixture of distorted corner and face-sharing MgSr2Mg10 cuboctahedra. There are a spread of Mg–Mg bond distances ranging from 2.97–3.27 Å. In the fourth Mg site, Mg is bonded in a distorted q6 geometry to three equivalent Sr and nine Mg atoms. There are three shorter (3.04 Å) and three longer (3.30 Å) Mg–Mg bond lengths. In the fifth Mg site, Mg is bonded to four Sr and eight Mg atoms to form a mixture of corner and face-sharing MgSr4Mg8 cuboctahedra. There are a spread of Mg–Mg bond distances ranging from 3.00–3.27 Å. In the sixth Mg site, Mg is bonded to three equivalent Sr and nine Mg atoms to form a mixture of distorted corner and face-sharing MgSr3Mg9 cuboctahedra. There are a spread of Mg–Mg bond distances ranging from 3.12–3.32 Å. In the seventh Mg site, Mg is bonded in a 11-coordinate geometry to three Sr and eight Mg atoms. There are two shorter (3.43 Å) and one longer (3.46 Å) Mg–Mg bond lengths. In the eighth Mg site, Mg is bonded in a distorted q6 geometry to three equivalent Sr and nine Mg atoms. All Mg–Mg bond lengths are 3.33 Å. In the ninth Mg site, Mg is bonded in a 12-coordinate geometry to three Sr and nine Mg atoms.