The Raman spectra of the crystalline and the amorphous pure drug film (Figure ) are consistent with those previously presented between 600 and 1900 cm -1 for form II and the amorphous form of RTV , including a sharp peak at 1660 cm -1 (C=O stretching) characteris c for form II, which is much smaller and broadened for the amorphous form. We are not aware of published Raman spectra of RTV at higher frequencies, but the CH stretch region was also dis nct for the two forms of RTV with peaks at 3059 cm -1 and 3097 cm -1 for the crystalline form and broader peaks centered at 2927 cm -1 and 3061 cm -1 for the amorphous form. In this region, PVPVA exhibited a peak at 2936 cm -1 and a pronounced shoulder at 2983 cm -1 .