Molecular mechanics calculations on carbonyl compounds. II. Open-chain ketones

Open-chain aliphatic ketones were studied with the molecular mechanics (MM4) force field. A total of seven compounds were examined. Structures were well fit, including moments of inertia. Rotational barriers, vibrational spectra, and dipole moments were also well fit. The overall root mean square errors for MM3 and MM4 were 0.27 and 0.18%, respectively, for the six moments of inertia (known experimentally for two compounds) and 31 and 20 cm(-1), respectively, for the vibrational frequencies (over 99 weighted modes). (C) 2001 John Wiley & Sons, Inc.