′�?, using a frequency of 295 cm−1, is attributed towards the stretching vibration of Ga–Se bonds. The two-phonon absorption on the 295 cm−1 phonon corresponds for the crystal IR absorption edge, as opposed to the residual absorption peak. Density functional theory computations show the residual absorption of the BGSe crystal https://baga4se7-crystal14578.azzablog.com/32924763/baga4se7-crystal-options