PaNi3 is beta Cu3Ti-like structured and crystallizes in the hexagonal P6_3/mmc space group. Pa(1) is bonded to twelve Ni(1,1) atoms to form PaNi12 cuboctahedra that share corners with six equivalent Pa(1)Ni12 cuboctahedra; corners with twelve Ni(1,1)Pa4Ni8 cuboctahedra; edges with eighteen Ni(1,1)Pa4Ni8 cuboctahedra; faces with eight equivalent Pa(1)Ni12 cuboctahedra; and faces with twelve Ni(1,1)Pa4Ni8 cuboctahedra. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to four equivalent Pa(1) and eight Ni(1,1) atoms to form distorted NiPa4Ni8 cuboctahedra that share corners with four equivalent Pa(1)Ni12 cuboctahedra; corners with fourteen Ni(1,1)Pa4Ni8 cuboctahedra; edges with six equivalent Pa(1)Ni12 cuboctahedra; edges with twelve Ni(1,1)Pa4Ni8 cuboctahedra; faces with four equivalent Pa(1)Ni12 cuboctahedra; and faces with sixteen Ni(1,1)Pa4Ni8 cuboctahedra. In the second Ni site, Ni(1) is bonded to four equivalent Pa(1) and eight Ni(1,1) atoms to form distorted NiPa4Ni8 cuboctahedra that share corners with four equivalent Pa(1)Ni12 cuboctahedra; corners with fourteen Ni(1,1)Pa4Ni8 cuboctahedra; edges with six equivalent Pa(1)Ni12 cuboctahedra; edges with twelve Ni(1,1)Pa4Ni8 cuboctahedra; faces with four equivalent Pa(1)Ni12 cuboctahedra; and faces with sixteen Ni(1,1)Pa4Ni8 cuboctahedra.
PaNi3 is beta Cu3Ti-like structured and crystallizes in the hexagonal P6_3/mmc space group. Pa(1) is bonded to twelve Ni(1,1) atoms to form PaNi12 cuboctahedra that share corners with six equivalent Pa(1)Ni12 cuboctahedra; corners with twelve Ni(1,1)Pa4Ni8 cuboctahedra; edges with eighteen Ni(1,1)Pa4Ni8 cuboctahedra; faces with eight equivalent Pa(1)Ni12 cuboctahedra; and faces with twelve Ni(1,1)Pa4Ni8 cuboctahedra. There are six shorter (2.63 Å) and six longer (2.85 Å) Pa(1)-Ni(1,1) bond lengths. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to four equivalent Pa(1) and eight Ni(1,1) atoms to form distorted NiPa4Ni8 cuboctahedra that share corners with four equivalent Pa(1)Ni12 cuboctahedra; corners with fourteen Ni(1,1)Pa4Ni8 cuboctahedra; edges with six equivalent Pa(1)Ni12 cuboctahedra; edges with twelve Ni(1,1)Pa4Ni8 cuboctahedra; faces with four equivalent Pa(1)Ni12 cuboctahedra; and faces with sixteen Ni(1,1)Pa4Ni8 cuboctahedra. There are a spread of Ni(1)-Ni(1,1) bond distances ranging from 2.51-2.77 Å. In the second Ni site, Ni(1) is bonded to four equivalent Pa(1) and eight Ni(1,1) atoms to form distorted NiPa4Ni8 cuboctahedra that share corners with four equivalent Pa(1)Ni12 cuboctahedra; corners with fourteen Ni(1,1)Pa4Ni8 cuboctahedra; edges with six equivalent Pa(1)Ni12 cuboctahedra; edges with twelve Ni(1,1)Pa4Ni8 cuboctahedra; faces with four equivalent Pa(1)Ni12 cuboctahedra; and faces with sixteen Ni(1,1)Pa4Ni8 cuboctahedra. Both Ni(1)-Ni(1) bond lengths are 2.77 Å.