Materials Data on Na5Si34 by Materials Project

Abstract

(Na)2Na3Si34 crystallizes in the trigonal R-3m space group. The structure is three-dimensional and consists of six sodium molecules and one Na3Si34 framework. In the Na3Si34 framework, Na is bonded in a 8-coordinate geometry to twenty Si atoms. There are a spread of Na–Si bond distances ranging from 3.21–3.40 Å. There are six inequivalent Si sites. In the first Si site, Si is bonded in a 7-coordinate geometry to three equivalent Na and four Si atoms. There are three shorter (2.39 Å) and one longer (2.40 Å) Si–Si bond lengths. In the second Si site, Si is bonded in a 6-coordinate geometry to two equivalent Na and four Si atoms. There are two shorter (2.38 Å) and two longer (2.39 Å) Si–Si bond lengths. In the third Si site, Si is bonded in a 7-coordinate geometry to three equivalent Na and four Si atoms. In the fourth Si site, Si is bonded in a 4-coordinate geometry to two equivalent Na and four Si atoms. There are two shorter (2.37 Å) and one longer (2.42 Å) Si–Si bond lengths. In the fifth Si site, Si is bonded in a 4-coordinate geometry to one Na and four Si atoms. There are one shorter (2.37 Å) and one longer (2.40 Å) Si–Si bond lengths. In the sixth Si site, Si is bonded in a 4-coordinate geometry to two equivalent Na and four Si atoms. Both Si–Si bond lengths are 2.37 Å.