Mössbauer and calorimetric studies of spin reorientation processes in Er2−xPrxFe14C

Abstract

The Er2−xPrxFe14C (x = 0.25, 0.5) poly crystalline compounds have been synthesized and investigated by means of X-ray diffraction, 57Fe Mössbauer spectroscopy and Differential Scanning Calorimetry (DSC). The influence of carbon on the spin reorientation phenomena with increasing praseodymium content was of special interest in these compounds. Investigations of spin reorientation phenomena were performed by means of 57Fe Mössbauer spectroscopy with a narrow step temperature scanning in the neighborhood of the spin reorientation temperature. Obtained Mössbauer spectra were analyzed using a procedure of simultaneous fitting and the transmission integral approach. Consistent description of Mossbauer spectra were obtained. Temperature dependencies of hyperfine interaction parameters and subspectra contributions were derived from fits and the transition temperatures were determined for all the compounds studied. DSC studies revealed weak thermal effect (heat absorption) during the transition process. Heat absorption was detected only for the compound with the lowest content of Pr (x = 0.25). The results obtained with different methods were analyzed and data were compared with those for Er2−xPrxFe14B series. The spin arrangement diagram was constructed.