Materials Data on U(SiAu)2 by Materials Project

Abstract

UAu2Si2 crystallizes in the tetragonal P4/nmm space group. The structure is three-dimensional. U6+ is bonded in a 8-coordinate geometry to eight Si4- atoms. There are four shorter (3.27 Å) and four longer (3.32 Å) U–Si bond lengths. There are two inequivalent Au1+ sites. In the first Au1+ site, Au1+ is bonded to four equivalent Si4- atoms to form a mixture of edge and corner-sharing AuSi4 tetrahedra. All Au–Si bond lengths are 2.57 Å. In the second Au1+ site, Au1+ is bonded in a 5-coordinate geometry to five Si4- atoms. There are one shorter (2.41 Å) and four longer (2.51 Å) Au–Si bond lengths. There are two inequivalent Si4- sites. In the first Si4- site, Si4- is bonded to four equivalent U6+ and four equivalent Au1+ atoms to form a mixture of distorted face and edge-sharing SiU4Au4 tetrahedra. In the second Si4- site, Si4- is bonded in a 5-coordinate geometry to four equivalent U6+ and five Au1+ atoms.