Comment on 'Frustrating magnetic interactions and broadened magnetic interactions in the edge--sharing CuO2 chains in La5Ca9Cu24O41.

Leidl, R., Selke, W.
Institut für Theoretische Physik, Technische Hochschule Aachen,
D-52056 Aachen, Germany


Using Monte Carlo techniques, we show that the two--dimensional anisotropic Heisenberg model reproducing nicely inelastic neutron scattering measurements on La5Ca9Cu24O41 (Matsuda et al., Phys. Rev. B68, 060406(R) (2003)) seems to be insufficient to describe correctly measurements on thermodynamic quantities like the magnetization or susceptibility. Possible reasons for the discrepancy are suggested.