RAMAN-SPECTROSCOPIC STUDY OF THE OH AND OD TORSION IN 1,2-DIHYDROXYBENZENE

Low-frequency Raman spectra of catechol and catechol-d2 have been measured for the melt and for the solid at different temperatures. Two different torsional transitions were observed for the OH tops, at 453 and 471 cm-1. The two-fold barriers calculated from these torsional frequencies are V2 = 1674 ± 19 cm-1 and V2 = 1953 ± 20 cm-1. Upon deuteration the torsional transitions are shifted to 305 cm-1 and 361 cm-1, and the torsional barriers obtained were V2 = 1482 ± 18 cm-1 and V2 = 2070 ± 21 cm-1. The difference between the barriers of the two tops is interpreted in terms of different hydrogen-bonding and deuterium-bonding environments. In solid catechol the deuterium bond is found to be twice as strong as the corresponding hydrogen bond. © 1979.