′�?, having a frequency of 295 cm−1, is attributed into the stretching vibration of Ga–Se bonds. The 2-phonon absorption in the 295 cm−1 phonon corresponds to the crystal IR absorption edge, as opposed to the residual absorption peak. Density purposeful principle computations show the residual absorption with the BGSe crystal https://garrettwcfgg.idblogz.com/33256509/about-baga4se7-crystal