′�?, that has a frequency of 295 cm−1, is attributed on the stretching vibration of Ga–Se bonds. The two-phonon absorption in the 295 cm−1 phonon corresponds towards the crystal IR absorption edge, as opposed to the residual absorption peak. Density functional theory computations demonstrate the residual absorption in the BGSe https://holdenqzbqz.glifeblog.com/31722685/how-much-you-need-to-expect-you-ll-pay-for-a-good-baga4se7-crystal