Materials Data on SiGe by Materials Project

Abstract

SiGe crystallizes in the monoclinic P2_1 space group. The structure is three-dimensional. there are eight inequivalent Ge4+ sites. In the first Ge4+ site, Ge4+ is bonded in a single-bond geometry to one Si4- atom. The Ge–Si bond length is 2.41 Å. In the second Ge4+ site, Ge4+ is bonded in a trigonal non-coplanar geometry to three Si4- atoms. All Ge–Si bond lengths are 2.42 Å. In the third Ge4+ site, Ge4+ is bonded in a single-bond geometry to one Si4- atom. The Ge–Si bond length is 2.42 Å. In the fourth Ge4+ site, Ge4+ is bonded in a trigonal non-coplanar geometry to three Si4- atoms. There are a spread of Ge–Si bond distances ranging from 2.42–2.44 Å. In the fifth Ge4+ site, Ge4+ is bonded in a single-bond geometry to one Si4- atom. The Ge–Si bond length is 2.43 Å. In the sixth Ge4+ site, Ge4+ is bonded in a trigonal non-coplanar geometry to three Si4- atoms. There are one shorter (2.42 Å) and two longer (2.43 Å) Ge–Si bond lengths. In the seventh Ge4+ site, Ge4+ is bonded in a trigonal non-coplanar geometry to three Si4- atoms. There are a spread of Ge–Si bond distances ranging from 2.42–2.44 Å. In the eighth Ge4+ site, Ge4+ is bonded in a single-bond geometry to one Si4- atom. The Ge–Si bond length is 2.41 Å. There are eight inequivalent Si4- sites. In the first Si4- site, Si4- is bonded to one Ge4+ and three Si4- atoms to form corner-sharing SiSi3Ge tetrahedra. There are one shorter (2.38 Å) and two longer (2.39 Å) Si–Si bond lengths. In the second Si4- site, Si4- is bonded to three Ge4+ and one Si4- atom to form corner-sharing SiSiGe3 tetrahedra. The Si–Si bond length is 2.38 Å. In the third Si4- site, Si4- is bonded to one Ge4+ and three Si4- atoms to form corner-sharing SiSi3Ge tetrahedra. There are one shorter (2.37 Å) and two longer (2.38 Å) Si–Si bond lengths. In the fourth Si4- site, Si4- is bonded to three Ge4+ and one Si4- atom to form corner-sharing SiSiGe3 tetrahedra. The Si–Si bond length is 2.36 Å. In the fifth Si4- site, Si4- is bonded to one Ge4+ and three Si4- atoms to form corner-sharing SiSi3Ge tetrahedra. In the sixth Si4- site, Si4- is bonded to three Ge4+ and one Si4- atom to form corner-sharing SiSiGe3 tetrahedra. In the seventh Si4- site, Si4- is bonded to three Ge4+ and one Si4- atom to form corner-sharing SiSiGe3 tetrahedra. In the eighth Si4- site, Si4- is bonded to one Ge4+ and three Si4- atoms to form corner-sharing SiSi3Ge tetrahedra.