Vibrational analysis of polyene chains. Assignments of the resonance Raman lines of poly (acetylene) and β‐carotene

Abstract
The normal frequencies and vibrational modes have been calculated for two models of an infinite polyene chain using a modified Urey‐Bradley force field. The vibrational modes giving rise to strong resonance Raman lines have been elucidated on the basis of the results of the calculation.