Temperature dependent high velocity resolution Mossbauer spectroscopic study of iron nickel phosphide microcrystals (rhabdites) extracted from Sikhote-Alin iron meteorite

Iron nickel phosphide microcrystals (rhabdites) extracted from Sikhote-Alin iron meteorite fragment were studied using Mossbauer spectroscopy with a high velocity resolution at various temperatures. Mossbauer spectra of rhabdites demonstrated superparamagnetic behavior. Low temperature rhabdite spectra were fitted using a model with six magnetic sextets two pairs of which were related to crystallographically non-equivalent sites M1, M2 and M3 occupied by Fe and Ni atoms in different ways. Temperature dependencies of correspondent magnetic hyperfine fields were evaluated. On the basis of relative areas of spectral components and results of rhabdite chemical analysis the average numbers of Fe and Ni atoms occupied the M1, M2 and M3 sites, respectively, were evaluated. (C) 2010 Elsevier B.V. All rights reserved.