Universal Single-Ion Physics in Spin–Orbit-Coupled d5 and d4 Ions
journal contributionposted on 05.11.2018, 11:49 by Hongcheng Lu, Juan R. Chamorro, Cheng Wan, Tyrel M. McQueen
We have identified six new 4d4 and 4d5 compounds with isolated RuCl6 octahedra, with formulas (HMA)4RuCl6·Cl (1; MA = methylamine), (HGly)4RuCl6·Cl (2; gly = glycine), (HGly)3RuCl6·2H2O (3), (NH4)2RuCl6 (4), (HPy)2RuCl6 (5; py = pyridine), and H2(4,4′-bpy)RuCl6 (6; 4,4′-bpy = 4,4′-bipyridine). We find that the temperature-dependent magnetization is well described by single-ion physics in the presence of spin–orbit coupling and negligible superexchange interactions. Further, we find that many compounds in the literature are also well described by single-ion physics, and our results demonstrate the importance of considering single-ion physics when evaluating candidate geometric frustrated magnets in the presence of spin–orbit coupling.