Influence de la conformation sur le champ de force etles modes de vibration des monohalogénocyclohexanes

Valence force fields and normal modes of vibration of axial and equatorial forms of four monohalogenated cyclohexanes are computed and compared. A new assignment of axial isomers and of the equatorial form of fluorocyclohexane is proposed. Both geometry and force field differences are necessary to explain rotational isomerism splittings. Normal modes of equatorial isomers are rather close to those of cyclohexane. Interactions between non-bonded atoms are found for the axial isomers.