Structure and magnetism of HoBaCo2O5+ \delta layered cobaltites with

In this paper we have studied, by means of high-resolution neutron powder diffraction and magnetic susceptibility, the structural and magnetic features of selected samples of the HoBaCo2O5+δ layered cobaltite in the low oxygen content range 0.02≤δ≤0.22. The results show a strong antiferromagnetic contribution at room temperature coupled to an intermediate spin state of the Co3+ ions.