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Even though it would be possible to calculate the line broadening for a given function, this is rarely done as there are several complication especially related to ordering and surfaces. Structural disorder in bond lengths, angles etc. will all modify the widths of the frequencies more significantly than the theoretical broadening. Thus, often if in computational studies the frequencies and intensities are simply listed for comparison to observed spectra, and the peaks are broadened with the use of a Gaussian or Lorentzian function maintaining the overall integrated intensity. A term often appearing related to the broadening is full width at half maximum (FWHM), which is an expression for the width of the peak between points on the curve that are half of the maximum amplitude.Single cite short citeID Cramer
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