Structural and Torsional Properties of o-Cresol and o-Cresol-OD as Obtained from Microwave Spectroscopy and ab Initio Calculations

✍ Scribed by A Welzel; A Hellweg; I Merke; W Stahl

• Publisher: Elsevier Science
• Year: 2002
• Tongue: English
• Weight: 164 KB
• Volume: 215
• Category: Article
• ISSN: 0022-2852
• DOI: 10.1006/jmsp.2002.8600

✦ Synopsis

The microwave spectra of o-cresol and of o-cresol-OD were assigned using molecular beam Fourier transform microwave (MB-FTMW) spectrometers in the frequency range of 3-40 GHz. Two conformers of o-cresol were measured where the hydroxy group is syn with respect to the methyl group in one case and anti in the other. The transitions of both conformers were split due to internal rotation of the methyl group. For syn-o-cresol we found the rotational constants A = 3249.45242(18) MHz, B = 2202.02546(18) MHz, C = 1323.66277( ) MHz, and the barrier to internal rotation of the methyl group V 3 = 7.912(46) kJ mol -1 . In the case of anti-o-cresol A = 3273.80084(18) MHz, B = 2196.26747(18) MHz, C = 1325.36424( ) MHz, and V 3 = 4.4256( ) kJ mol -1 was obtained. Moreover we were able to determine the quartic centrifugal distortion constants, the angle between the internal rotor axes, and the inertial a axes, and, for the deuterated species, additionally the deuterium nuclear quadrupole coupling constants.