Knowledge Bank

The Fourier self-deconvolution technique was developed by Kauppinen et al, using a Lorentz band shape to enhance intrinsically overlapped bands in ir spectra by narrowing the bandwidth of bands so that the components in a massive absorption become separated.1 In this presentation, the theory of Fourier deconvolution using Cauchy-Gauss product functions is developed that permits to enhance an experimental infrared spectra more adequately than using pure Cauchy (or Lorentz) functions. Two methods can be used to obtain the inverse Fourier transform of the lineshape function: an analytical and a numerical method. The numerical method gives some errors which limit the degree of enhancement. The analytical method overcomes these difficulties but necessitates a mathematical development. The numerical method is the only way to obtain an inverse Fourier transform of an experimental spectrum, and some aliasing is introduced by the algorithm used. The infrared spectra of the carbonyl containing compounds are used to illustrate the effectiveness of the procedure described