Ni3CuO4 is Caswellsilverite-like structured and crystallizes in the orthorhombic Cmmm space group. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to two equivalent O(1) and four equivalent O(2) atoms to form NiO6 octahedra that share corners with six equivalent Cu(1)O6 octahedra, edges with two equivalent Ni(1)O6 octahedra, edges with two equivalent Cu(1)O6 octahedra, and edges with eight equivalent Ni(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-3°. In the second Ni site, Ni(2) is bonded to two equivalent O(2) and four equivalent O(1) atoms to form NiO6 octahedra that share corners with six equivalent Ni(2)O6 octahedra, edges with four equivalent Ni(1)O6 octahedra, edges with four equivalent Ni(2)O6 octahedra, and edges with four equivalent Cu(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 4-11°. Cu(1) is bonded to two equivalent O(1) and four equivalent O(2) atoms to form CuO6 octahedra that share corners with six equivalent Ni(1)O6 octahedra, edges with two equivalent Ni(1)O6 octahedra, edges with two equivalent Cu(1)O6 octahedra, and edges with eight equivalent Ni(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-3°. There are two inequivalent O sites. In the first O site, O(1) is bonded to one Ni(1), four equivalent Ni(2), and one Cu(1) atom to form OCuNi5 octahedra that share corners with six equivalent O(1)CuNi5 octahedra, edges with four equivalent O(1)CuNi5 octahedra, and edges with eight equivalent O(2)Cu2Ni4 octahedra. The corner-sharing octahedra are not tilted. In the second O site, O(2) is bonded to two equivalent Ni(1), two equivalent Ni(2), and two equivalent Cu(1) atoms to form OCu2Ni4 octahedra that share corners with six equivalent O(2)Cu2Ni4 octahedra, edges with four equivalent O(2)Cu2Ni4 octahedra, and edges with eight equivalent O(1)CuNi5 octahedra. The corner-sharing octahedra are not tilted.
Ni3CuO4 is Caswellsilverite-like structured and crystallizes in the orthorhombic Cmmm space group. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to two equivalent O(1) and four equivalent O(2) atoms to form NiO6 octahedra that share corners with six equivalent Cu(1)O6 octahedra, edges with two equivalent Ni(1)O6 octahedra, edges with two equivalent Cu(1)O6 octahedra, and edges with eight equivalent Ni(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-3°. Both Ni(1)-O(1) bond lengths are 2.02 Å. All Ni(1)-O(2) bond lengths are 2.13 Å. In the second Ni site, Ni(2) is bonded to two equivalent O(2) and four equivalent O(1) atoms to form NiO6 octahedra that share corners with six equivalent Ni(2)O6 octahedra, edges with four equivalent Ni(1)O6 octahedra, edges with four equivalent Ni(2)O6 octahedra, and edges with four equivalent Cu(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 4-11°. Both Ni(2)-O(2) bond lengths are 2.22 Å. All Ni(2)-O(1) bond lengths are 2.08 Å. Cu(1) is bonded to two equivalent O(1) and four equivalent O(2) atoms to form CuO6 octahedra that share corners with six equivalent Ni(1)O6 octahedra, edges with two equivalent Ni(1)O6 octahedra, edges with two equivalent Cu(1)O6 octahedra, and edges with eight equivalent Ni(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-3°. Both Cu(1)-O(1) bond lengths are 2.42 Å. All Cu(1)-O(2) bond lengths are 2.02 Å. There are two inequivalent O sites. In the first O site, O(1) is bonded to one Ni(1), four equivalent Ni(2), and one Cu(1) atom to form OCuNi5 octahedra that share corners with six equivalent O(1)CuNi5 octahedra, edges with four equivalent O(1)CuNi5 octahedra, and edges with eight equivalent O(2)Cu2Ni4 octahedra. The corner-sharing octahedra are not tilted. In the second O site, O(2) is bonded to two equivalent Ni(1), two equivalent Ni(2), and two equivalent Cu(1) atoms to form OCu2Ni4 octahedra that share corners with six equivalent O(2)Cu2Ni4 octahedra, edges with four equivalent O(2)Cu2Ni4 octahedra, and edges with eight equivalent O(1)CuNi5 octahedra. The corner-sharing octahedra are not tilted.