Hyperfine structure of several soils from western Hubei and Inner Mongolia studied by Mössbauer spectroscopy

Abstract

Soil samples taken from Xilamuren Grassland, Resonant Sand Bay, Inner Mongolia, and Yichang, western Hubei Province were investigated by Mossbauer spectroscopy at room temperature and 20 K. This was supplemented with phase identification and elemental analysis to obtain information about the composition and structure types of Fe-containing compounds. The samples collected from both Xilamuren Grassland and Resonant Sand Bay, Inner Mongolia were found to have small amount of iron 1%–2%. The main phases were determined as silica, albite, and microcline. Two or three dominant doublets were observed in the Mossbauer spectra of these samples, respectively and identified as corresponding to the valence states of Fe2+ and Fe3+. A sextet observed in all the spectra is attributed to the hematite phase. Low temperature Mossbauer measurements have revealed Morin transition.