Materials Data on Cs7NaSi8 by Materials Project

Abstract

CsCs6NaSi8 crystallizes in the cubic Pa-3 space group. The structure is three-dimensional and consists of four cesium molecules and one Cs6NaSi8 framework. In the Cs6NaSi8 framework, Cs1+ is bonded in a 6-coordinate geometry to six Si1- atoms. There are a spread of Cs–Si bond distances ranging from 3.67–3.95 Å. Na1+ is bonded in a 6-coordinate geometry to six equivalent Si1- atoms. All Na–Si bond lengths are 3.00 Å. There are two inequivalent Si1- sites. In the first Si1- site, Si1- is bonded in a 9-coordinate geometry to six equivalent Cs1+ and three equivalent Si1- atoms. All Si–Si bond lengths are 2.42 Å. In the second Si1- site, Si1- is bonded in a 1-coordinate geometry to four equivalent Cs1+, one Na1+, and three Si1- atoms. Both Si–Si bond lengths are 2.47 Å.