The Low Temperature Study of $Ln[Fe(CN)_6] \cdot xH_2O$ Rare-Earth Ferricyanides, Ln=Pr,La

We present magnetic and structural properties of $Ln[Fe(CN)_6] \cdot xH_2O$, Ln = Pr, La single crystals investigated by means of elastic neutron diffraction and heat capacity down to 0.03 K and susceptibility and magnetization measurements. The susceptibility data were taken on the commercial SQUID magnetometer (Quantum Design) in the range between 2 K and 30 K and in fields up to 5 T. Our low temperature neutron diffraction data taken in a zero field rules out some of antiferromagnetic models suggested in the literature.