Materials Data on Ta3SiNi8 by Materials Project

Abstract

Ta3Ni8Si crystallizes in the trigonal P3m1 space group. The structure is three-dimensional. there are three inequivalent Ta sites. In the first Ta site, Ta is bonded in a 9-coordinate geometry to twelve Ni and three equivalent Si atoms. There are a spread of Ta–Ni bond distances ranging from 2.71–2.82 Å. All Ta–Si bond lengths are 2.84 Å. In the second Ta site, Ta is bonded in a 12-coordinate geometry to twelve Ni atoms. There are a spread of Ta–Ni bond distances ranging from 2.74–2.79 Å. In the third Ta site, Ta is bonded in a 6-coordinate geometry to twelve Ni and one Si atom. There are a spread of Ta–Ni bond distances ranging from 2.69–2.92 Å. The Ta–Si bond length is 2.91 Å. There are four inequivalent Ni sites. In the first Ni site, Ni is bonded to three equivalent Ta, six Ni, and three equivalent Si atoms to form NiTa3Si3Ni6 cuboctahedra that share corners with twelve NiTa4Si2Ni6 cuboctahedra, edges with six equivalent NiTa3Si3Ni6 cuboctahedra, and faces with twenty NiTa6Ni6 cuboctahedra. There are three shorter (2.37 Å) and three longer (2.39 Å) Ni–Ni bond lengths. All Ni–Si bond lengths are 2.76 Å. In the second Ni site, Ni is bonded to six Ta and six Ni atoms to form NiTa6Ni6 cuboctahedra that share corners with twelve NiTa5SiNi6 cuboctahedra, edges with six equivalent NiTa6Ni6 cuboctahedra, and faces with twenty NiTa3Si3Ni6 cuboctahedra. There are three shorter (2.36 Å) and three longer (2.38 Å) Ni–Ni bond lengths. In the third Ni site, Ni is bonded to four Ta, six Ni, and two equivalent Si atoms to form distorted NiTa4Si2Ni6 cuboctahedra that share corners with eighteen NiTa3Si3Ni6 cuboctahedra, edges with six NiTa4Si2Ni6 cuboctahedra, and faces with eighteen NiTa3Si3Ni6 cuboctahedra. There are two shorter (2.34 Å) and two longer (2.42 Å) Ni–Ni bond lengths. Both Ni–Si bond lengths are 2.91 Å. In the fourth Ni site, Ni is bonded to five Ta, six Ni, and one Si atom to form NiTa5SiNi6 cuboctahedra that share corners with eighteen NiTa3Si3Ni6 cuboctahedra, edges with six NiTa4Si2Ni6 cuboctahedra, and faces with eighteen NiTa3Si3Ni6 cuboctahedra. There are two shorter (2.33 Å) and two longer (2.44 Å) Ni–Ni bond lengths. The Ni–Si bond length is 2.56 Å. Si is bonded in a 10-coordinate geometry to four Ta and twelve Ni atoms.