QUADRUPOLE SPLITTING DISTRIBUTIONS IN TRICLINIC ASTROPHYLLITE

Abstract

The mineral, triclinic astrophyllite, was investigated using the Mossbauer effect. The Mossbauer spectra of triclinic astrophyllite at 298 K, 180 K and 90 K were measured, and the quadrupole splitting distributions (QSDs) from the Mossbauer spectra were obtained by using a Voigt-based method for line shape analysis. The distortion parameters, the variances of the octahedral bond angles for triclinic astrophyllite, were calculated, and a site assignment was tentatively given based on the distortion parameters. According to the ratios of ferric to total iron obtained by the Mossbauer effect and the mean value of f(Fe3+(O))/f(Fe2+(O)), the chemical formula of triclinic astrophyllite was rewritten.