′�?, having a frequency of 295 cm−1, is attributed to the stretching vibration of Ga–Se bonds. The two-phonon absorption from the 295 cm−one phonon corresponds into the crystal IR absorption edge, as opposed to the residual absorption peak. Density functional theory computations clearly show which the residual absorption on the https://baga4se7crystal24679.ageeksblog.com/31732602/baga4se7-crystal-an-overview