Vibrational energy carbonyl group

Maciel et have observed an isotope effect of —0-28 p.p.m. on the chemical shift of the carbonyl group in acetone- /g with respect to that of the carbonyl shift of acetone. The authors discuss the results in terms of vibrational zero-point energies, and in addition the paper describes a useful method of observing resonances using a direct field—frequency lock system. 

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