Odd Moments of the Cross-Correlation Function for Library Searching of Infrared Spectra

Abstract

The odd moments of the autocorrelation function are zero, and the moments of the cross-correlation function for an unknown spectrum with a library entry have been used here to select the best fits. The use of the first moment or average wavenumber in six separate spectral ranges requires only 12 values per library entry, and 24 values are required per library entry if twelve separate ranges are used. The odd moment methods were found to yield results for searches with both library and experimental spectra that were comparable to correlation coefficients in selection of the proper chemical class for the unknown spectra and in making of the proper identification.