Crystal Structure of U2Pt2Sn: A New Derivative of the Tetragonal U3Si2- Type Structure.

The crystal structure of the new ternary stannide U2Pt2Sn has been investigated by both X-ray powder diffraction and electron diffraction. It crystallizes in a tetragonal unit cell with a= 768.1(1) pm and c= 739.1(1) pm. This crystal structure is a new superstructure of the tetragonal U3Si2-type which appears on account of the existence of short Pt–Pt distances. The crystal structure of U2Pt2Sn is described taking into consideration those of UPt and UPt2Sn.