DOE OSTI2020
Lu2Ru3Si5 crystallizes in the tetragonal P4/mnc space group. The structure is three-dimensional. Lu3+ is bonded in a 9-coordinate geometry to nine Si+2.40- atoms. There are a spread of Lu–Si bond distances ranging from 2.81–3.13 Å. There are two inequivalent Ru2+ sites. In the first Ru2+ site, Ru2+ is bonded to six Si+2.40- atoms to form a mixture of distorted corner, edge, and face-sharing RuSi6 octahedra. The corner-sharing octahedral tilt angles are 48°. There are a spread of Ru–Si bond distances ranging from 2.43–2.49 Å. In the second Ru2+ site, Ru2+ is bonded in a distorted hexagonal planar geometry to six Si+2.40- atoms. There are four shorter (2.40 Å) and two longer (2.65 Å) Ru–Si bond lengths. There are three inequivalent Si+2.40- sites. In the first Si+2.40- site, Si+2.40- is bonded in a 11-coordinate geometry to four equivalent Lu3+, three Ru2+, and four Si+2.40- atoms. There are two shorter (2.56 Å) and two longer (2.79 Å) Si–Si bond lengths. In the second Si+2.40- site, Si+2.40- is bonded in a 9-coordinate geometry to four equivalent Lu3+, four equivalent Ru2+, and one Si+2.40- atom. The Si–Si bond length is 2.73 Å. In the third Si+2.40- site, Si+2.40- is bonded in a 7-coordinate geometry to three equivalent Lu3+, four Ru2+, and two equivalent Si+2.40- atoms.