′�?, by using a frequency of 295 cm−1, is attributed on the stretching vibration of Ga–Se bonds. The 2-phonon absorption of your 295 cm−1 phonon corresponds towards the crystal IR absorption edge, rather than the residual absorption peak. Density functional idea computations demonstrate the residual absorption in the BGSe crystal https://baga4se7crystal07484.suomiblog.com/not-known-facts-about-baga4se7-crystal-48407355