Ni3Ta is beta Cu3Ti structured and crystallizes in the orthorhombic Pmmn space group. Ta(1) is bonded to four equivalent Ni(1) and eight equivalent Ni(2) atoms to form TaNi12 cuboctahedra that share corners with two equivalent Ta(1)Ni12 cuboctahedra, corners with eight equivalent Ni(1)Ta4Ni8 cuboctahedra, corners with eight equivalent Ni(2)Ta4Ni8 cuboctahedra, edges with six equivalent Ta(1)Ni12 cuboctahedra, edges with twelve equivalent Ni(2)Ta4Ni8 cuboctahedra, faces with six equivalent Ta(1)Ni12 cuboctahedra, faces with six equivalent Ni(1)Ta4Ni8 cuboctahedra, and faces with eight equivalent Ni(2)Ta4Ni8 cuboctahedra. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to four equivalent Ta(1) and eight equivalent Ni(2) atoms to form distorted NiTa4Ni8 cuboctahedra that share corners with two equivalent Ni(1)Ta4Ni8 cuboctahedra, corners with eight equivalent Ta(1)Ni12 cuboctahedra, corners with eight equivalent Ni(2)Ta4Ni8 cuboctahedra, edges with six equivalent Ni(1)Ta4Ni8 cuboctahedra, edges with twelve equivalent Ni(2)Ta4Ni8 cuboctahedra, faces with six equivalent Ta(1)Ni12 cuboctahedra, faces with six equivalent Ni(1)Ta4Ni8 cuboctahedra, and faces with eight equivalent Ni(2)Ta4Ni8 cuboctahedra. In the second Ni site, Ni(2) is bonded to four equivalent Ta(1), four equivalent Ni(1), and four equivalent Ni(2) atoms to form distorted NiTa4Ni8 cuboctahedra that share corners with four equivalent Ta(1)Ni12 cuboctahedra, corners with four equivalent Ni(1)Ta4Ni8 cuboctahedra, corners with ten equivalent Ni(2)Ta4Ni8 cuboctahedra, edges with six equivalent Ta(1)Ni12 cuboctahedra, edges with six equivalent Ni(1)Ta4Ni8 cuboctahedra, edges with six equivalent Ni(2)Ta4Ni8 cuboctahedra, faces with four equivalent Ta(1)Ni12 cuboctahedra, faces with four equivalent Ni(1)Ta4Ni8 cuboctahedra, and faces with twelve equivalent Ni(2)Ta4Ni8 cuboctahedra.
Ni3Ta is beta Cu3Ti structured and crystallizes in the orthorhombic Pmmn space group. Ta(1) is bonded to four equivalent Ni(1) and eight equivalent Ni(2) atoms to form TaNi12 cuboctahedra that share corners with two equivalent Ta(1)Ni12 cuboctahedra, corners with eight equivalent Ni(1)Ta4Ni8 cuboctahedra, corners with eight equivalent Ni(2)Ta4Ni8 cuboctahedra, edges with six equivalent Ta(1)Ni12 cuboctahedra, edges with twelve equivalent Ni(2)Ta4Ni8 cuboctahedra, faces with six equivalent Ta(1)Ni12 cuboctahedra, faces with six equivalent Ni(1)Ta4Ni8 cuboctahedra, and faces with eight equivalent Ni(2)Ta4Ni8 cuboctahedra. There are two shorter (2.54 Å) and two longer (2.58 Å) Ta(1)-Ni(1) bond lengths. There are a spread of Ta(1)-Ni(2) bond distances ranging from 2.55-2.61 Å. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to four equivalent Ta(1) and eight equivalent Ni(2) atoms to form distorted NiTa4Ni8 cuboctahedra that share corners with two equivalent Ni(1)Ta4Ni8 cuboctahedra, corners with eight equivalent Ta(1)Ni12 cuboctahedra, corners with eight equivalent Ni(2)Ta4Ni8 cuboctahedra, edges with six equivalent Ni(1)Ta4Ni8 cuboctahedra, edges with twelve equivalent Ni(2)Ta4Ni8 cuboctahedra, faces with six equivalent Ta(1)Ni12 cuboctahedra, faces with six equivalent Ni(1)Ta4Ni8 cuboctahedra, and faces with eight equivalent Ni(2)Ta4Ni8 cuboctahedra. There are a spread of Ni(1)-Ni(2) bond distances ranging from 2.49-2.68 Å. In the second Ni site, Ni(2) is bonded to four equivalent Ta(1), four equivalent Ni(1), and four equivalent Ni(2) atoms to form distorted NiTa4Ni8 cuboctahedra that share corners with four equivalent Ta(1)Ni12 cuboctahedra, corners with four equivalent Ni(1)Ta4Ni8 cuboctahedra, corners with ten equivalent Ni(2)Ta4Ni8 cuboctahedra, edges with six equivalent Ta(1)Ni12 cuboctahedra, edges with six equivalent Ni(1)Ta4Ni8 cuboctahedra, edges with six equivalent Ni(2)Ta4Ni8 cuboctahedra, faces with four equivalent Ta(1)Ni12 cuboctahedra, faces with four equivalent Ni(1)Ta4Ni8 cuboctahedra, and faces with twelve equivalent Ni(2)Ta4Ni8 cuboctahedra. There is one shorter (2.53 Å) and three longer (2.54 Å) Ni(2)-Ni(2) bond lengths.