An extensive study of natural and synthetic Fe-bearing sphalerites (Fe-content ranging from 0.005 afu to 0.250 afu) has been carried out through the combined investigations of the temperature dependence of the magnetic susceptibility and of the Fe-57 Mossbauer spectroscopic features. Magnetic susceptibility measurements evidence, in the low temperature regime, the presence of clustered Fe even in the most diluted samples, whereas all the Mossbauer spectra are described in terms of variable proportions of three components, namely one single and two doublets absorption, centred at the same isomer shift, relative to Fe ions and to different Fe clusters, respectively. The comparison of all the experimental results points out a self-affinity of Fe ions in sphalerite favoured by the superexchange interaction, which stabilises the formation of clusters even in diluted samples and may be related to both macroscopic inhomogeneous distribution and crystal zoning.
Short-range order of Fe2+ in sphalerite by Fe-57 Mossbauer spectroscopy and magnetic susceptibility / F., Di Benedetto; Andreozzi, Giovanni Battista; G. P., Bernardini; M., Borgheresi; A., Caneschi; C., Cipriani; D., Gatteschi; M., Romanelli. - In: PHYSICS AND CHEMISTRY OF MINERALS. - ISSN 0342-1791. - 32:(2005), pp. 339-348. [10.1007/s00269-005-0002-9]
Short-range order of Fe2+ in sphalerite by Fe-57 Mossbauer spectroscopy and magnetic susceptibility
ANDREOZZI, Giovanni Battista;
2005
Abstract
An extensive study of natural and synthetic Fe-bearing sphalerites (Fe-content ranging from 0.005 afu to 0.250 afu) has been carried out through the combined investigations of the temperature dependence of the magnetic susceptibility and of the Fe-57 Mossbauer spectroscopic features. Magnetic susceptibility measurements evidence, in the low temperature regime, the presence of clustered Fe even in the most diluted samples, whereas all the Mossbauer spectra are described in terms of variable proportions of three components, namely one single and two doublets absorption, centred at the same isomer shift, relative to Fe ions and to different Fe clusters, respectively. The comparison of all the experimental results points out a self-affinity of Fe ions in sphalerite favoured by the superexchange interaction, which stabilises the formation of clusters even in diluted samples and may be related to both macroscopic inhomogeneous distribution and crystal zoning.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
