′�?, with a frequency of 295 cm−one, is attributed to your stretching vibration of Ga–Se bonds. The 2-phonon absorption in the 295 cm−one phonon corresponds to your crystal IR absorption edge, in lieu of the residual absorption peak. Density practical theory computations show the residual absorption of your BGSe crystal https://cruzylllk.qowap.com/92088745/detailed-notes-on-baga4se7-crystal