′�?, with a frequency of 295 cm−1, is attributed for the stretching vibration of Ga–Se bonds. The two-phonon absorption of the 295 cm−one phonon corresponds for the crystal IR absorption edge, instead of the residual absorption peak. Density purposeful concept computations show which the residual absorption in the BGSe crystal https://baga4se7-crystal75295.ivasdesign.com/54320636/5-simple-techniques-for-baga4se7-crystal