Materials Data on Pm3Cu by Materials Project
Pm3Cu is Uranium Silicide-like structured and crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. there are two inequivalent Pm sites. In the first Pm site, Pm is bonded to eight Pm and four equivalent Cu atoms to form distorted PmPm8Cu4 cuboctahedra that share corners with twelve equivalent PmPm8Cu4 cuboctahedra, edges with eight equivalent PmPm8Cu4 cuboctahedra, edges with eight equivalent CuPm12 cuboctahedra, faces with four equivalent CuPm12 cuboctahedra, and faces with ten equivalent PmPm8Cu4 cuboctahedra. There are four shorter (3.31 Å) and four longer (3.44 Å) Pm–Pm bond lengths. All Pm–Cu bond lengths are 3.44 Å. In the second Pm site, Pm is bonded in a distorted square co-planar geometry to eight equivalent Pm and four equivalent Cu atoms. All Pm–Cu bond lengths are 3.31 Å. Cu is bonded to twelve Pm atoms to form CuPm12 cuboctahedra that share corners with four equivalent CuPm12 cuboctahedra, edges with eight equivalent CuPm12 cuboctahedra, edges with sixteen equivalent PmPm8Cu4 cuboctahedra, faces with four equivalent CuPm12 cuboctahedra, and faces with eight equivalent PmPm8Cu4 cuboctahedra.