Ho2Co3Si5 crystallizes in the monoclinic C2/c space group. Ho(1) is bonded in a 13-coordinate geometry to two equivalent Co(1), three equivalent Co(2), two equivalent Si(1), two equivalent Si(2), two equivalent Si(4), and four equivalent Si(3) atoms. There are two inequivalent Co sites. In the first Co site, Co(1) is bonded to four equivalent Ho(1), two equivalent Co(1), one Si(1), one Si(2), and four equivalent Si(3) atoms to form a mixture of distorted face and corner-sharing CoHo4Co2Si6 cuboctahedra. In the second Co site, Co(2) is bonded in a 8-coordinate geometry to three equivalent Ho(1), one Si(1), one Si(2), one Si(3), and two equivalent Si(4) atoms. There are four inequivalent Si sites. In the first Si site, Si(1) is bonded in a 11-coordinate geometry to four equivalent Ho(1), one Co(1), two equivalent Co(2), two equivalent Si(2), and two equivalent Si(3) atoms. In the second Si site, Si(2) is bonded in a 11-coordinate geometry to four equivalent Ho(1), one Co(1), two equivalent Co(2), two equivalent Si(1), and two equivalent Si(3) atoms. In the third Si site, Si(3) is bonded in a 9-coordinate geometry to four equivalent Ho(1), one Co(2), two equivalent Co(1), one Si(1), and one Si(2) atom. In the fourth Si site, Si(4) is bonded in a 8-coordinate geometry to four equivalent Ho(1) and four equivalent Co(2) atoms.
Ho2Co3Si5 crystallizes in the monoclinic C2/c space group. Ho(1) is bonded in a 13-coordinate geometry to two equivalent Co(1), three equivalent Co(2), two equivalent Si(1), two equivalent Si(2), two equivalent Si(4), and four equivalent Si(3) atoms. Both Ho(1)-Co(1) bond lengths are 3.23 Å. There is one shorter (2.95 Å) and two longer (2.99 Å) Ho(1)-Co(2) bond lengths. There is one shorter (3.02 Å) and one longer (3.04 Å) Ho(1)-Si(1) bond length. There is one shorter (3.03 Å) and one longer (3.04 Å) Ho(1)-Si(2) bond length. There is one shorter (2.99 Å) and one longer (3.00 Å) Ho(1)-Si(4) bond length. There are a spread of Ho(1)-Si(3) bond distances ranging from 2.82-3.06 Å. There are two inequivalent Co sites. In the first Co site, Co(1) is bonded to four equivalent Ho(1), two equivalent Co(1), one Si(1), one Si(2), and four equivalent Si(3) atoms to form a mixture of distorted face and corner-sharing CoHo4Co2Si6 cuboctahedra. Both Co(1)-Co(1) bond lengths are 2.75 Å. The Co(1)-Si(1) bond length is 2.54 Å. The Co(1)-Si(2) bond length is 2.53 Å. There are two shorter (2.31 Å) and two longer (2.32 Å) Co(1)-Si(3) bond lengths. In the second Co site, Co(2) is bonded in a 8-coordinate geometry to three equivalent Ho(1), one Si(1), one Si(2), one Si(3), and two equivalent Si(4) atoms. The Co(2)-Si(1) bond length is 2.29 Å. The Co(2)-Si(2) bond length is 2.28 Å. The Co(2)-Si(3) bond length is 2.24 Å. Both Co(2)-Si(4) bond lengths are 2.31 Å. There are four inequivalent Si sites. In the first Si site, Si(1) is bonded in a 11-coordinate geometry to four equivalent Ho(1), one Co(1), two equivalent Co(2), two equivalent Si(2), and two equivalent Si(3) atoms. Both Si(1)-Si(2) bond lengths are 2.75 Å. Both Si(1)-Si(3) bond lengths are 2.47 Å. In the second Si site, Si(2) is bonded in a 11-coordinate geometry to four equivalent Ho(1), one Co(1), two equivalent Co(2), two equivalent Si(1), and two equivalent Si(3) atoms. Both Si(2)-Si(3) bond lengths are 2.47 Å. In the third Si site, Si(3) is bonded in a 9-coordinate geometry to four equivalent Ho(1), one Co(2), two equivalent Co(1), one Si(1), and one Si(2) atom. In the fourth Si site, Si(4) is bonded in a 8-coordinate geometry to four equivalent Ho(1) and four equivalent Co(2) atoms.