′�?, having a frequency of 295 cm−1, is attributed towards the stretching vibration of Ga–Se bonds. The two-phonon absorption of your 295 cm−1 phonon corresponds into the crystal IR absorption edge, rather then the residual absorption peak. Density useful theory computations clearly show the residual absorption in the BGSe crystal https://baga4se7crystal24678.thechapblog.com/32017549/5-easy-facts-about-baga4se7-crystal-described