Materials Data on Cs(NpSe3)2 by Materials Project

Abstract

Cs(NpSe3)2 crystallizes in the orthorhombic Immm space group. The structure is three-dimensional. Cs1+ is bonded to eight equivalent Se2- atoms to form face-sharing CsSe8 hexagonal bipyramids. All Cs–Se bond lengths are 3.77 Å. Np+5.50+ is bonded in a 8-coordinate geometry to eight Se2- atoms. There are a spread of Np–Se bond distances ranging from 2.89–2.96 Å. There are two inequivalent Se2- sites. In the first Se2- site, Se2- is bonded to four equivalent Np+5.50+ atoms to form a mixture of distorted corner and edge-sharing SeNp4 trigonal pyramids. In the second Se2- site, Se2- is bonded in a 2-coordinate geometry to two equivalent Cs1+, two equivalent Np+5.50+, and two equivalent Se2- atoms. There are one shorter (2.68 Å) and one longer (2.81 Å) Se–Se bond lengths.