Materials Data on CeUSi4 by Materials Project
UCeSi4 is hexagonal omega structure-derived structured and crystallizes in the tetragonal I-4m2 space group. The structure is three-dimensional. U5+ is bonded to twelve Si2- atoms to form USi12 cuboctahedra that share edges with four equivalent USi12 cuboctahedra, edges with eight equivalent CeSi12 cuboctahedra, faces with four equivalent USi12 cuboctahedra, and faces with four equivalent CeSi12 cuboctahedra. There are eight shorter (3.05 Å) and four longer (3.08 Å) U–Si bond lengths. Ce3+ is bonded to twelve Si2- atoms to form CeSi12 cuboctahedra that share edges with four equivalent CeSi12 cuboctahedra, edges with eight equivalent USi12 cuboctahedra, faces with four equivalent USi12 cuboctahedra, and faces with four equivalent CeSi12 cuboctahedra. There are eight shorter (3.07 Å) and four longer (3.12 Å) Ce–Si bond lengths. There are two inequivalent Si2- sites. In the first Si2- site, Si2- is bonded in a 9-coordinate geometry to two equivalent U5+, four equivalent Ce3+, and three Si2- atoms. There are two shorter (2.32 Å) and one longer (2.40 Å) Si–Si bond lengths. In the second Si2- site, Si2- is bonded in a 9-coordinate geometry to four equivalent U5+, two equivalent Ce3+, and three Si2- atoms. The Si–Si bond length is 2.31 Å.