Spin-wave analysis of pseudo-one-dimensional antiferromagnet CsMnCl3·2H2O

The low-temperature specific heat, sublattice magnetization, zero-point spin reduction, and ground-state energy of CsMn${\mathrm{Cl}}_3$·${2\mathrm{H}}_2$O have been confronted with a spin-wave calculation, which was based upon the particular magnetic structure of this compound. In this numerical calculation the effect of small interchain interactions and a temperature-dependent anisotropy gap have been included. A good agreement with the experimental heat capacity was obtained for an intrachain interaction $\frac{J}{k}=-3.0\mathrm{}$ K and a ratio of the inter-to intrachain interaction $\left|\frac{J^{\prime }}{J}\right|=8\mathrm{}\times {10}^{-3\mathrm{}}$. These values compare favorably with the results from other studies. The predicted sublattice magnetization, including the zero-point spin reduction of 19%, is in good agreement with the experimental evidence. The calculated ground-state energy corresponds with the value obtained by direct integration of the experimental magnetic heat capacity. It was concluded that unrenormalized spin-wave theory offers a fair description of the magnetic behavior of CsMn${\mathrm{Cl}}_3$·${2\mathrm{H}}_2$O up to $\sim 0.6T_N$.