Temperature dependent hyperfine interactions in the intermetallic compounds YFe3, TbFe3and ErFe3

The temperature dependent hyperfine interactions of 57 Fe nuclei in the intermetallic compounds RFe 3 , where R=Y, Tb and Er have been studied using the Mossbauer effect. It is found that YFe 3 and TbFe 3 remain magnetized along a b axis at all temperatures whereas ErFe 3 is magnetized along a c axis despite a marked change in the character of the Mossbauer spectrum between 4.2K and 77K. It is also argued that there is no substantial difference in the electronic configurations of the iron atoms at their two main inequivalent crystallographic sites, as witnessed by the temperature dependence of the total shift and the hyperfine fields. The quadrupole parameters were found to be temperature independent and to originate primarily from the lattice. The analogy between similar properties of the RFe 2 and the RFe 3 is also presented.