EXPERIMENTAL AND THEORETICAL-STUDIES ON THE MAGNETIC-BEHAVIOR OF ND3+IN NDPO4

The monoclinic monazite-type single crystals of NdPO4 were grown by fl ux technique. The molar principal susceptibilities (chi(1) and chi(3)) of the crystal have been measured in the temperature range 300-13 K; the principal magnetic anisotropies (chi(1) - chi(2), chi(1) - chi(3)) were obtained from the observed anisotropies in different modes of su spension of the crystal. The ionic susceptibilities are computed using the spectroscopic crystal-held parameters of Rukmini et al. (J. Phys. : Condens. Matter 6 (1994) 5919). The observed crystal susceptibilitie s are correlated to the ionic values determining the proper orientatio n of the ionic susceptibilities with respect to that of the crystal; t he agreement between the experimental and theoretical values is excell ent which incidentally rules out ordering effects of any consequence d own to 13 K. g-factors computed for the ground doublet are found to be highly anisotropic. The electronic-heat capacity at different tempera tures was calculated using the Stark energies which did not show any S chottky-type anomalies.