′�?, having a frequency of 295 cm−1, is attributed towards the stretching vibration of Ga–Se bonds. The two-phonon absorption of the 295 cm−one phonon corresponds to your crystal IR absorption edge, rather then the residual absorption peak. Density useful concept computations show which the residual absorption with the BGSe crystal https://baga4se7-crystal61582.post-blogs.com/53576737/baga4se7-crystal-options