Materials Data on U2Cu3Si4Ni by Materials Project
U2NiCu3Si4 crystallizes in the tetragonal P-4m2 space group. The structure is three-dimensional. U5+ is bonded in a distorted body-centered cubic geometry to eight Si4- atoms. There are four shorter (3.02 Å) and four longer (3.03 Å) U–Si bond lengths. Ni2+ is bonded to four equivalent Si4- atoms to form NiSi4 tetrahedra that share corners with four equivalent NiSi4 tetrahedra and edges with four equivalent CuSi4 tetrahedra. All Ni–Si bond lengths are 2.34 Å. There are two inequivalent Cu+1.33+ sites. In the first Cu+1.33+ site, Cu+1.33+ is bonded to four equivalent Si4- atoms to form a mixture of edge and corner-sharing CuSi4 tetrahedra. All Cu–Si bond lengths are 2.40 Å. In the second Cu+1.33+ site, Cu+1.33+ is bonded to four equivalent Si4- atoms to form CuSi4 tetrahedra that share corners with four equivalent CuSi4 tetrahedra and edges with four equivalent NiSi4 tetrahedra. All Cu–Si bond lengths are 2.34 Å. There are two inequivalent Si4- sites. In the first Si4- site, Si4- is bonded in a 9-coordinate geometry to four equivalent U5+, two equivalent Ni2+, two equivalent Cu+1.33+, and one Si4- atom. The Si–Si bond length is 2.34 Å. In the second Si4- site, Si4- is bonded in a 9-coordinate geometry to four equivalent U5+, four equivalent Cu+1.33+, and one Si4- atom.