Short range ordering in the modified honeycomb lattice compound SrHo ₂O₄

The low temperature behaviour of single crystalline SrHo₂O ₄ has been characterized by dc magnetic susceptibility, heat capacity, and neutron scattering experiments. Our results show that despite the lack of magnetic long-ranged ordering in the presence of strong antiferromagnetic correlations, SrHo₂O₄ does not order down to 1.8K. Elastic neutron scattering experiments show prominent magnetic diffuse scattering correlated with a broad feature in the dc susceptibility at T = 4K, indicative of magnetic short-ranged ordering of the Ho³ spins. Inelastic neutron scattering shows the presence of five crystal field levels up to 80K in energy, in agreement with the integration of the magnetic specific heat component yielding Rln5 entropy release. The magnetic short-ranged ordering is fitted to a nearest neighbour interaction model with good agreement.