Structure and Magnetism of HoBaCo2O5+delta Layered Cobaltites with 0.02<delta<0.22

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+delta layered cobaltite in the low oxygen content range (0.02<delta<0.22). The results shows a strong antiferromagnetic contribution at room temperature coupled to an intermediate spin state of the Co3+ ions.