Resonance raman results in polyacetylene

Abstract

Abstract Inelastic light scattering experiments with tunable lasers give unique information on the morphology and excitations in undoped polyacetylene. The characteristics of these spectra and the current state of their interpretation are reviewed here. In the case of trans (CH)x, the model relating the Raman and absorption profiles to an inhomogeneous distribution of conjugation lengths is described and quantitative implications presented. New results reported include the following: measurements and analysis of Raman profiles indicating the large contribution from short conjugation lengths in trans (CH)X; the lack of direct evidence for photogenerated solitons in recent two-beam Raman spectra (there may be evidence for soliton formation in the excited state linewidth, however); and the markedly different resonance Raman behavior and photoluminescence in cis (CH)X and short segments of trans (CH)X.