Ho2Ti3Si4 crystallizes in the tetragonal P4_12_12 space group. Ho(1) is bonded in a 7-coordinate geometry to three equivalent Si(2) and four equivalent Si(1) atoms. There are two inequivalent Ti sites. In the first Ti site, Ti(1) is bonded to two equivalent Si(1) and four equivalent Si(2) atoms to form distorted corner-sharing TiSi6 octahedra. The corner-sharing octahedral tilt angles are 53°. In the second Ti site, Ti(2) is bonded in a 6-coordinate geometry to three equivalent Si(1) and three equivalent Si(2) atoms. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded in a 9-coordinate geometry to four equivalent Ho(1), one Ti(1), three equivalent Ti(2), and one Si(2) atom. In the second Si site, Si(2) is bonded in a 9-coordinate geometry to three equivalent Ho(1), two equivalent Ti(1), three equivalent Ti(2), and one Si(1) atom.
Ho2Ti3Si4 crystallizes in the tetragonal P4_12_12 space group. Ho(1) is bonded in a 7-coordinate geometry to three equivalent Si(2) and four equivalent Si(1) atoms. There are a spread of Ho(1)-Si(2) bond distances ranging from 2.85-2.93 Å. There are a spread of Ho(1)-Si(1) bond distances ranging from 2.82-3.11 Å. There are two inequivalent Ti sites. In the first Ti site, Ti(1) is bonded to two equivalent Si(1) and four equivalent Si(2) atoms to form distorted corner-sharing TiSi6 octahedra. The corner-sharing octahedral tilt angles are 53°. Both Ti(1)-Si(1) bond lengths are 2.79 Å. There are two shorter (2.68 Å) and two longer (2.78 Å) Ti(1)-Si(2) bond lengths. In the second Ti site, Ti(2) is bonded in a 6-coordinate geometry to three equivalent Si(1) and three equivalent Si(2) atoms. There are a spread of Ti(2)-Si(1) bond distances ranging from 2.60-2.73 Å. There are a spread of Ti(2)-Si(2) bond distances ranging from 2.55-2.66 Å. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded in a 9-coordinate geometry to four equivalent Ho(1), one Ti(1), three equivalent Ti(2), and one Si(2) atom. The Si(1)-Si(2) bond length is 2.49 Å. In the second Si site, Si(2) is bonded in a 9-coordinate geometry to three equivalent Ho(1), two equivalent Ti(1), three equivalent Ti(2), and one Si(1) atom.