Materials Data on Pm3Cr by Materials Project
Pm3Cr 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 Cr atoms to form distorted PmPm8Cr4 cuboctahedra that share corners with twelve equivalent PmPm8Cr4 cuboctahedra, edges with eight equivalent PmPm8Cr4 cuboctahedra, edges with eight equivalent CrPm12 cuboctahedra, faces with four equivalent CrPm12 cuboctahedra, and faces with ten equivalent PmPm8Cr4 cuboctahedra. There are four shorter (3.41 Å) and four longer (3.48 Å) Pm–Pm bond lengths. All Pm–Cr bond lengths are 3.48 Å. In the second Pm site, Pm is bonded in a distorted square co-planar geometry to eight equivalent Pm and four equivalent Cr atoms. All Pm–Cr bond lengths are 3.41 Å. Cr is bonded to twelve Pm atoms to form CrPm12 cuboctahedra that share corners with four equivalent CrPm12 cuboctahedra, edges with eight equivalent CrPm12 cuboctahedra, edges with sixteen equivalent PmPm8Cr4 cuboctahedra, faces with four equivalent CrPm12 cuboctahedra, and faces with eight equivalent PmPm8Cr4 cuboctahedra.