The CH2Cl torsional barrier of benzyl chloride studied by gas-phase absorption spectroscopy and ab initio calculations

✍ Scribed by J.M. Hollas; J.J.C. Teixeira-Dias; P.J.A. Ribeiro-Claro

• Publisher: Elsevier Science
• Year: 1989
• Tongue: English
• Weight: 323 KB
• Volume: 157
• Category: Article
• ISSN: 0009-2614
• DOI: 10.1016/0009-2614(89)87202-1

✦ Synopsis

The high-resolution gas-phase 269 nm absorption spectrum of benzyl chloride in the O-O region is reported. A long sequence on the high wavenumber side of the O-O band, assigned to the torsional mode, points to an internal rotation barrier larger in the excited state than in the ground state. This can be explained by a stronger interaction between the x-electron system and the chlorine atom. Ab initio calculations at the 6-31G level yield an & CHtCl torsional barrier of Il.1 kJ mol-' in benxyl chloride. A barrier of 22.6 kJ mol-' is estimated in S, from the gas-phase absorption spectrum.