General expression for the Voigt function that is of special interest for applied spectroscopy

The purpose of this work is twofold. First we obtain a series expansion for the Voigt function that is valid for all values of the dimensionless parameter a (a measure of the ratio between the Lorentzian and Gaussian widths). Furthermore, the resulting coefficients are independent of the generalized coordinate b (the wavelength measured in units of the Gaussian width). In the second place, we fit an experimental "shaped bell" curve to a Voigt profile using certain theoretical restrictions that relate the maximum height and the full width at half-maximum.