qspec.models.VoigtDerivative  (  )[source]

The first derivative of a Voigt peak function of the form $$\begin{aligned} f(x, \Gamma, \sigma) &= -\frac{\sqrt{2}\delta\nu}{\sigma}\frac{\mathrm{Re}[z w(z)]} {\mathrm{Re}[w(i\Gamma/(\sqrt{8}\sigma))]}, \quad z = \frac{2x + i\Gamma}{\sqrt{8}\sigma},\\[2ex] \delta\nu &= 0.5346\Gamma + \sqrt{0.2166\Gamma^2 + 8\log(2)\sigma^2}, \end{aligned}$$ with the complex Faddeeva function $w$.