Spin reorientation and magnetocaloric effect study in HoAl2 by a microscopic model Hamiltonian

The magnetocaloric properties in HoAl2 were fully investigated using a model Hamiltonian that takes into account the exchange magnetic interaction and the crystalline electrical field anisotropy. We have shown that spin reorientation has an influence on the magnetocaloric effect. An anomalous valley was predicted to exist in the magnetocaloric curves, and it was ascribed to the spin reorientation. All theoretical results were obtained using the proper model parameters found in the literature for this compound. (C) 2007 American Institute of Physics.