Mössbauer line-sharpening: Application to magnetically-split spectra

Abstract

The contrast in a Mössbauer spectrum can be enhanced by a model-independent method of line sharpening, due to Afanas'ev and Tsymbal, which employs higher powers of Lorenztian lines. We have investigated the applicability of this process to the⁵⁷Fe spectrum of a new, ternary rare-earth intermetallic Nd₂(Fe, Ti)₁₉. Fitting the processed spectrum gives a smallerx² value than a simple Lorentzian fit to the original data due to the deviation from the pure Lorentzian line shape in the spectrum caused by statistical fluctuations in the local chemical environment of the⁵⁷Fe nuclei. However, we find that the use of the Pearson VII line shape gives a better fit to the spectrum than either the standard Lorentzians or the sharpened, higher-power Lorentzians. The line-sharpening process based on higher-power Lorentzians appears to be of limited use in the study of complex, overlapping magnetic spectra.