Ho4Co3 crystallizes in the trigonal P-3 space group. There are two inequivalent Ho sites. In the first Ho site, Ho(1) is bonded in a 7-coordinate geometry to two equivalent Co(1) and five equivalent Co(2) atoms. In the second Ho site, Ho(2) is bonded in a 4-coordinate geometry to one Co(3) and three equivalent Co(2) atoms. There are three inequivalent Co sites. In the first Co site, Co(1) is bonded in a 9-coordinate geometry to six equivalent Ho(1) and three equivalent Co(2) atoms. In the second Co site, Co(2) is bonded in a 9-coordinate geometry to three equivalent Ho(2), five equivalent Ho(1), and one Co(1) atom. In the third Co site, Co(3) is bonded in a 6-coordinate geometry to six equivalent Ho(2) atoms.
Ho4Co3 crystallizes in the trigonal P-3 space group. There are two inequivalent Ho sites. In the first Ho site, Ho(1) is bonded in a 7-coordinate geometry to two equivalent Co(1) and five equivalent Co(2) atoms. There is one shorter (2.85 Å) and one longer (2.86 Å) Ho(1)-Co(1) bond length. There are a spread of Ho(1)-Co(2) bond distances ranging from 2.93-2.98 Å. In the second Ho site, Ho(2) is bonded in a 4-coordinate geometry to one Co(3) and three equivalent Co(2) atoms. The Ho(2)-Co(3) bond length is 2.82 Å. There are a spread of Ho(2)-Co(2) bond distances ranging from 2.77-3.10 Å. There are three inequivalent Co sites. In the first Co site, Co(1) is bonded in a 9-coordinate geometry to six equivalent Ho(1) and three equivalent Co(2) atoms. All Co(1)-Co(2) bond lengths are 2.28 Å. In the second Co site, Co(2) is bonded in a 9-coordinate geometry to three equivalent Ho(2), five equivalent Ho(1), and one Co(1) atom. In the third Co site, Co(3) is bonded in a 6-coordinate geometry to six equivalent Ho(2) atoms.