Knowledge Bank

High resolution optical spectra of all-trans 1,3,5,7-octatetraene have been obtained in polycrystalline n-hexane and n-octane at $4,2\circ K$. Long progressions in the single and double bond vibrational modes are seem along with some low frequency torsional modes. The frequencies of the single and double bond modes are found to increase in the fluorescent state. Some results for chromatographically pure 3-cis 1,3,5,7-octatet-raene and 3,5-dicis 1,3,5,7-octatetraene will also be presented.