′�?, with a frequency of 295 cm−1, is attributed to the stretching vibration of Ga–Se bonds. The 2-phonon absorption on the 295 cm−1 phonon corresponds into the crystal IR absorption edge, rather then the residual absorption peak. Density purposeful principle computations display which the residual absorption in the BGSe crystal https://feliximlmk.bloginder.com/33423757/not-known-details-about-baga4se7-crystal