Materials Data on Mg3Si8Ir3 by Materials Project
Mg3Ir3Si8 crystallizes in the cubic F-43m space group. The structure is three-dimensional. there are three inequivalent Mg2+ sites. In the first Mg2+ site, Mg2+ is bonded in a 9-coordinate geometry to nine Si2- atoms. There are three shorter (3.04 Å) and six longer (3.06 Å) Mg–Si bond lengths. In the second Mg2+ site, Mg2+ is bonded in a distorted cuboctahedral geometry to twelve equivalent Si2- atoms. All Mg–Si bond lengths are 3.15 Å. In the third Mg2+ site, Mg2+ is bonded in a 12-coordinate geometry to twelve equivalent Si2- atoms. All Mg–Si bond lengths are 2.97 Å. Ir+3.33+ is bonded in a 6-coordinate geometry to six Si2- atoms. There are four shorter (2.42 Å) and two longer (2.46 Å) Ir–Si bond lengths. There are two inequivalent Si2- sites. In the first Si2- site, Si2- is bonded in a 9-coordinate geometry to four Mg2+, two equivalent Ir+3.33+, and three equivalent Si2- atoms. There are one shorter (2.42 Å) and two longer (2.62 Å) Si–Si bond lengths. In the second Si2- site, Si2- is bonded in a distorted trigonal planar geometry to three equivalent Mg2+ and three equivalent Ir+3.33+ atoms.