PsdVoigt1-FitFunc
While Vogit peak function is the convolution of a Gaussian curve G(x) and a Lorentzian curve L(x), the Pseudo-Voigt peak function is an approximation of the Voigt peak function which instead using a linear-combination of Gaussian curve G(x) and a Lorentzian curve L(x).
Origin provides two types of Pseudo-Vogit peak functions: PsdVogit1 and PsdVogit2. When using PsdVogit1, you can only specify one FWHM value denoted as w which will be shared between Gaussian curve G(x) and a Lorentzian curve L(x); while with PsdVogit2, you can specify two distinct FWHM values wG for Gaussian curve G(x) and wL for Lorentzian curve L(x).
Number: 5
Names: y0, xc, A, w, mu
Meanings: y0 = offset, xc = center, A = area, w = FWHM, mu = profile shape factor
Lower Bounds: w > 0.0
Upper Bounds: none
nlf_psdvoigt1(x,y0,xc,A,w,mu)
FITFUNC\PSDVGT1.FDF
Spectroscopy