Magnetic properties of quasi-one-dimensional antiferromagnets (Y1−xNdx)2BaNiO5 (x=1, 0.15)

We present the magnetic properties of (Y 1− x Nd x ) 2 BaNiO 5 ( x =1, 0.15) investigated by means of specific heat, magnetic susceptibility, and spectroscopic measurements. Magnetic ordering occurs at 47 K and 13 K in the compounds with x =1 and x =0.15, respectively. We estimate the magnetic contribution of the neodymium subsystem to magnetization and specific heat using temperature dependences of the splitting of ground Kramers doublet of Nd 3+ ion obtained from spectroscopic experiment. We show that both Nd–Ni and Nd–Nd interactions should be taken into account. An origin of the observed spin-glass state below ∼5 K and a contribution of the Ni chain breaks to the magnetization and specific heat are discussed.