Absorption spectra of crystalline thiophthene

摘要: Abstract The near ultraviolet absorption spectra of crystalline thiophthene have been measured in polarised light at temperatures down to 4–6 K. show that only the Davydov component located higher energies remains broad low temperature. nature this broadening is discussed terms downward inter-band phonon scattering from upper optical level by a librational phonon. A comparison experimental data and theoretical calculations energy levels polarisation ratios based on dipole—dipole approximation has carried out, direction π* ← π electronic transition which lies molecular plane defined.