Materials Data on Y2Fe4Si9 by Materials Project

Y2Fe4Si9 crystallizes in the trigonal P-3m1 space group. The structure is three-dimensional. Y is bonded in a 6-coordinate geometry to three equivalent Fe and eight Si atoms. All Y–Fe bond lengths are 3.21 Å. There are a spread of Y–Si bond distances ranging from 2.87–3.20 Å. There are two inequivalent Fe sites. In the first Fe site, Fe is bonded in a 7-coordinate geometry to ten Si atoms. There are a spread of Fe–Si bond distances ranging from 2.31–2.69 Å. In the second Fe site, Fe is bonded in a 10-coordinate geometry to three equivalent Y and seven Si atoms. There are four shorter (2.31 Å) and three longer (2.46 Å) Fe–Si bond lengths. There are five inequivalent Si sites. In the first Si site, Si is bonded in a 10-coordinate geometry to three equivalent Y, three equivalent Fe, and four Si atoms. There are one shorter (2.40 Å) and three longer (2.65 Å) Si–Si bond lengths. In the second Si site, Si is bonded in a 6-coordinate geometry to three equivalent Y, three equivalent Fe, and three equivalent Si atoms. All Si–Si bond lengths are 2.64 Å. In the third Si site, Si is bonded in a 4-coordinate geometry to one Y, four equivalent Fe, and six Si atoms. All Si–Si bond lengths are 2.50 Å. In the fourth Si site, Si is bonded in a 4-coordinate geometry to one Y, four equivalent Fe, and six Si atoms. All Si–Si bond lengths are 2.66 Å. In the fifth Si site, Si is bonded in a 8-coordinate geometry to six equivalent Fe and eight Si atoms.