Materials Data on NpSi by Materials Project

Abstract

NpSi crystallizes in the orthorhombic Cmcm space group. The structure is three-dimensional. there are two inequivalent Np4+ sites. In the first Np4+ site, Np4+ is bonded to six equivalent Si4- atoms to form distorted edge-sharing NpSi6 pentagonal pyramids. There are two shorter (2.90 Å) and four longer (2.93 Å) Np–Si bond lengths. In the second Np4+ site, Np4+ is bonded in a 8-coordinate geometry to eight equivalent Si4- atoms. There are four shorter (2.95 Å) and four longer (3.07 Å) Np–Si bond lengths. Si4- is bonded in a 9-coordinate geometry to seven Np4+ and two equivalent Si4- atoms. There are one shorter (2.43 Å) and one longer (2.45 Å) Si–Si bond lengths.