Materials Data on Nb4Si7Ni4 by Materials Project

Abstract

(Nb2Ni2Si3)2Si crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional and consists of two Si ribbons oriented in the (0, 0, 1) direction and one Nb2Ni2Si3 framework. In each Si ribbon, Si+1.71- is bonded in a linear geometry to two equivalent Si+1.71- atoms. There are one shorter (2.27 Å) and one longer (2.34 Å) Si–Si bond lengths. In the Nb2Ni2Si3 framework, Nb2+ is bonded in a 5-coordinate geometry to five Si+1.71- atoms. There are a spread of Nb–Si bond distances ranging from 2.67–2.70 Å. Ni1+ is bonded in a water-like geometry to two equivalent Si+1.71- atoms. Both Ni–Si bond lengths are 2.30 Å. There are three inequivalent Si+1.71- sites. In the first Si+1.71- site, Si+1.71- is bonded in a distorted hexagonal planar geometry to four equivalent Nb2+ and two equivalent Si+1.71- atoms. Both Si–Si bond lengths are 2.56 Å. In the second Si+1.71- site, Si+1.71- is bonded in a hexagonal planar geometry to two equivalent Nb2+ and four equivalent Ni1+ atoms. In the third Si+1.71- site, Si+1.71- is bonded in a hexagonal planar geometry to four equivalent Nb2+ and two equivalent Si+1.71- atoms.