Extended pseudo-Voigt function for approximating the Voigt profile

  title={Extended pseudo-Voigt function for approximating the Voigt profile},
  author={Takashi Ida and Masaya Ando and Hideo Toraya},
  journal={Journal of Applied Crystallography},
The formula of the pseudo-Voigt function expressed by a weighted sum of Gaussian and Lorentzian functions is extended by adding two other types of peak functions in order to improve the accuracy when approximating the Voigt profile. The full width at half-maximum (FWHM) values and mixing parameters of the Gaussian, the Lorentzian and the other two component functions in the extended formula can be approximated by polynomials of a parameter ρ = ΓL/(ΓG + ΓL), where ΓG and ΓL are the FWHM values… 

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