Abstract: | The study of the linear and nonlinear optical properties of Zn Ge P2 based on density functional theory has been carried out. In order to get a more physical picture in the infrared region, terms which are considered as the phonon effect were added to the calculated refractive dispersion curves. The phonon-corrected calculation curves show excellent agreement with experimental refractive indexes, which gives a better comprehension of the linear optical proprieties in the transparent region. The static nonlinear optical susceptibility was investigated using approaches based on the sum over states and the2 n + 1 theorem methods. Both of the results of these two methods reasonably coincided with the experimental results. |