Betamethasone: Low Temperature FTIR Measurement

Résumé fourni par la source

Betamethasone (BM) is characterized by FTIR spectroscopy in KBr pellet at temperatures ranging between RT (300 K) and 103 K, for the first time. Very clear spectral changes are observed in the characteristic stretching regions 2700-3700 cm -1 and 1550-1750 cm -1 , upon temperature variation. Observed data is compared with the computed data obtained at DFT(B3LYP)/6-311++G(d,p) level of theory. Tentative assignments are provided for some selected observed peaks based on the comparison between experiments and the theory. A possible phase transition is suggested to occur at low temperatures below 280 K.