Materials Data on Ta3Cr8Si by Materials Project

Abstract

Ta3Cr8Si is Hexagonal Laves-derived structured and 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 6-coordinate geometry to one Ta, twelve Cr, and three equivalent Si atoms. The Ta–Ta bond length is 3.05 Å. There are a spread of Ta–Cr bond distances ranging from 2.78–2.86 Å. All Ta–Si bond lengths are 2.96 Å. In the second Ta site, Ta is bonded in a 12-coordinate geometry to four Ta and twelve Cr atoms. All Ta–Ta bond lengths are 2.97 Å. There are a spread of Ta–Cr bond distances ranging from 2.84–2.87 Å. In the third Ta site, Ta is bonded in a 1-coordinate geometry to three equivalent Ta, twelve Cr, and one Si atom. There are a spread of Ta–Cr bond distances ranging from 2.84–2.89 Å. The Ta–Si bond length is 2.94 Å. There are four inequivalent Cr sites. In the first Cr site, Cr is bonded to three equivalent Ta, six Cr, and three equivalent Si atoms to form CrTa3Cr6Si3 cuboctahedra that share corners with twelve CrTa4Cr6Si2 cuboctahedra, edges with six equivalent CrTa3Cr6Si3 cuboctahedra, and faces with twenty CrTa6Cr6 cuboctahedra. There are three shorter (2.42 Å) and three longer (2.44 Å) Cr–Cr bond lengths. All Cr–Si bond lengths are 2.84 Å. In the second Cr site, Cr is bonded to six Ta and six Cr atoms to form CrTa6Cr6 cuboctahedra that share corners with twelve CrTa4Cr6Si2 cuboctahedra, edges with six equivalent CrTa6Cr6 cuboctahedra, and faces with twenty CrTa3Cr6Si3 cuboctahedra. All Cr–Cr bond lengths are 2.47 Å. In the third Cr site, Cr is bonded to four Ta, six Cr, and two equivalent Si atoms to form CrTa4Cr6Si2 cuboctahedra that share corners with eighteen CrTa3Cr6Si3 cuboctahedra, edges with six CrTa5Cr6Si cuboctahedra, and faces with eighteen CrTa3Cr6Si3 cuboctahedra. There are two shorter (2.38 Å) and two longer (2.46 Å) Cr–Cr bond lengths. Both Cr–Si bond lengths are 2.83 Å. In the fourth Cr site, Cr is bonded to five Ta, six Cr, and one Si atom to form CrTa5Cr6Si cuboctahedra that share corners with eighteen CrTa3Cr6Si3 cuboctahedra, edges with six CrTa5Cr6Si cuboctahedra, and faces with eighteen CrTa3Cr6Si3 cuboctahedra. There are two shorter (2.35 Å) and two longer (2.49 Å) Cr–Cr bond lengths. The Cr–Si bond length is 2.82 Å. Si is bonded in a 10-coordinate geometry to four Ta and twelve Cr atoms.