DOE OSTI2020
Y(PtSi)2 crystallizes in the tetragonal P4/nmm space group. The structure is three-dimensional. Y is bonded in a 12-coordinate geometry to eight Pt and eight Si atoms. There are four shorter (3.21 Å) and four longer (3.27 Å) Y–Pt bond lengths. There are four shorter (3.17 Å) and four longer (3.24 Å) Y–Si bond lengths. There are two inequivalent Pt sites. In the first Pt site, Pt is bonded to four equivalent Y and four equivalent Si atoms to form distorted PtY4Si4 tetrahedra that share corners with twelve equivalent SiY4Pt4 tetrahedra, edges with two equivalent SiY4Pt4 tetrahedra, edges with four equivalent PtY4Si4 tetrahedra, and faces with four equivalent PtY4Si4 tetrahedra. All Pt–Si bond lengths are 2.50 Å. In the second Pt site, Pt is bonded in a 9-coordinate geometry to four equivalent Y and five Si atoms. There are one shorter (2.38 Å) and four longer (2.43 Å) Pt–Si bond lengths. There are two inequivalent Si sites. In the first Si site, Si is bonded to four equivalent Y and four equivalent Pt atoms to form distorted SiY4Pt4 tetrahedra that share corners with twelve equivalent PtY4Si4 tetrahedra, edges with two equivalent PtY4Si4 tetrahedra, edges with four equivalent SiY4Pt4 tetrahedra, and faces with four equivalent SiY4Pt4 tetrahedra. In the second Si site, Si is bonded in a 9-coordinate geometry to four equivalent Y and five Pt atoms.