Materials Data on Nd4Si7 by Materials Project
Nd4Si7 crystallizes in the orthorhombic Pmm2 space group. The structure is three-dimensional. there are four inequivalent Nd3+ sites. In the first Nd3+ site, Nd3+ is bonded in a 8-coordinate geometry to eight Si+1.71- atoms. There are a spread of Nd–Si bond distances ranging from 3.05–3.11 Å. In the second Nd3+ site, Nd3+ is bonded to twelve Si+1.71- atoms to form a mixture of face and edge-sharing NdSi12 cuboctahedra. There are a spread of Nd–Si bond distances ranging from 3.08–3.18 Å. In the third Nd3+ site, Nd3+ is bonded to twelve Si+1.71- atoms to form a mixture of face and edge-sharing NdSi12 cuboctahedra. There are a spread of Nd–Si bond distances ranging from 3.09–3.23 Å. In the fourth Nd3+ site, Nd3+ is bonded in a distorted q4 geometry to ten Si+1.71- atoms. There are a spread of Nd–Si bond distances ranging from 3.10–3.20 Å. There are seven inequivalent Si+1.71- sites. In the first Si+1.71- site, Si+1.71- is bonded in a 8-coordinate geometry to six Nd3+ and two equivalent Si+1.71- atoms. Both Si–Si bond lengths are 2.42 Å. In the second Si+1.71- site, Si+1.71- is bonded in a 9-coordinate geometry to six Nd3+ and three Si+1.71- atoms. There are one shorter (2.33 Å) and two longer (2.38 Å) Si–Si bond lengths. In the third Si+1.71- site, Si+1.71- is bonded in a 9-coordinate geometry to six Nd3+ and three Si+1.71- atoms. The Si–Si bond length is 2.36 Å. In the fourth Si+1.71- site, Si+1.71- is bonded in a 9-coordinate geometry to six Nd3+ and three Si+1.71- atoms. The Si–Si bond length is 2.31 Å. In the fifth Si+1.71- site, Si+1.71- is bonded in a 9-coordinate geometry to six Nd3+ and three Si+1.71- atoms. Both Si–Si bond lengths are 2.39 Å. In the sixth Si+1.71- site, Si+1.71- is bonded in a 9-coordinate geometry to six Nd3+ and three Si+1.71- atoms. In the seventh Si+1.71- site, Si+1.71- is bonded in a 7-coordinate geometry to six Nd3+ and one Si+1.71- atom.