STATISTICAL-METHOD FOR THE IDENTIFICATION OF PEAK MOVEMENT IN SPECTRAL DATA - APPLICATION TO X-RAY-DIFFRACTION PATTERNS OF MANGANESE OXYHYDROXIDES

A fully automated statistical procedure is described for identifying s pectral peaks moving in response to a variable parameter. The method i s based upon the measurement of intensity at a given point in the spec trum. The variation of intensity in the spectrum at this given point i s considered in relation to the variable parameter via a linear regres sion analysis. If the peak does not move, then the values of intensity versus the variable parameter should show a linear relationship. On t he other hand, if there is a peak shifting through this fixed point wi th change in the variable parameter then the data should show nonlinea rity which can be readily identified statistically. The method was app lied to the analysis of x-ray diffraction spectra for manganese oxyhyd roxides reduced chemically to produce a range of values of MnIII/(MnII I + MnIV). Samples contained shifting peaks which were identified by t he method described.