Infrared Quantitative Analysis in the Fourier Domain: Processing Vector Representations

Abstract

The methodologies for forming orthogonal vector representations of transformed infrared spectra of pure components in multicomponent systems are developed. Either the Gram-Schmidt orthogonalization method or factor analysis can be used to generate the vector representations; both give equivalent results when one vector representation per component is generated. The results of processing data in the Fourier domain using both orthogonalization methods are compared with those obtained by processing in the spectral domain for the following three systems: (1) simulated spectra; (2) real spectra with dissimilar features; and (3) real spectra with very similar features. In all cases, processing in the Fourier domain produces the optimum results while requiring a minimum amount of operator contributions.