Vibration Spectra and Molecular Structure II. The Force Constants of the C–C and C–O Bonds in Organic Molecules

Abstract

Force constants are calculated from known vibration frequencies for several of the simpler organic molecules by an approximate method involving neglect of the interactions between motions of hydrogen atoms and other atoms. Frequency expressions are given for several special forms of the triatomic molecule, and the C–C and C–O force constants are calculated for ethane, propane, cyclopropane, ethylene oxide, ethyl alcohol, isobutane, dimethyl ether, and methyl alcohol. The values obtained are, in general, in the neighborhood of 3.8 and 4.5×10⁵ dynes/cm, respectively.