Materials Data on Pm3Np by Materials Project
NpPm3 is beta Cu3Ti-like structured and crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. Np is bonded to twelve equivalent Pm atoms to form NpPm12 cuboctahedra that share corners with six equivalent NpPm12 cuboctahedra, corners with twelve equivalent PmPm8Np4 cuboctahedra, edges with eighteen equivalent PmPm8Np4 cuboctahedra, faces with eight equivalent NpPm12 cuboctahedra, and faces with twelve equivalent PmPm8Np4 cuboctahedra. There are six shorter (3.52 Å) and six longer (3.58 Å) Np–Pm bond lengths. Pm is bonded to four equivalent Np and eight equivalent Pm atoms to form PmPm8Np4 cuboctahedra that share corners with four equivalent NpPm12 cuboctahedra, corners with fourteen equivalent PmPm8Np4 cuboctahedra, edges with six equivalent NpPm12 cuboctahedra, edges with twelve equivalent PmPm8Np4 cuboctahedra, faces with four equivalent NpPm12 cuboctahedra, and faces with sixteen equivalent PmPm8Np4 cuboctahedra. There are a spread of Pm–Pm bond distances ranging from 3.53–3.64 Å.