′�?, that has a frequency of 295 cm−1, is attributed for the stretching vibration of Ga–Se bonds. The two-phonon absorption of your 295 cm−1 phonon corresponds towards the crystal IR absorption edge, instead of the residual absorption peak. Density purposeful principle computations present the residual absorption with the BGSe crystal https://baga4s7-crystal19730.nizarblog.com/32920731/the-best-side-of-baga4se7-crystal