CALCULATION OF RESONANCE RAMAN EXCITATION PROFILES FOR SOLUBLE AND SOLID TRANSPOLYACETYLENE

On the basis of previously developed theory, a quantitative analysis o f the experimental data for sliced RREPs of soluble and solid trans-PA is undertaken. The effect of inhomogeneous environmental broadening o f RREPs of a solute molecule due to the solvent-molecule interactions and of molecules in the solid due to differences in chain lengths is i nvestigated. The role of the diagonal and non-diagonal terms of the sc attering matrix is discussed. The method is applied to the analysis of experimental data of Cataliotti et al. for soluble trans-PA (R.S. Cat aliotti, G. Paliani, G. Dellepiane, S. Fuse, S. Destri, L. Piseri, R. Tubino, J. Chem. Phys. 82 (1985) 2223) and of Lauchlan et al. for soli d trans-PA (L. Lauchlan, S.P. Chen, S. Etemad, M. Kletter, A.J. Heeger , A.G. MacDiarmid, Phys. Rev. B 27 (1983) 2301). In both cases the maj or contribution to the broadening of the RREPs comes from an inhomogen eous distribution of the electronic energies. (C) 1998 Elsevier Scienc e B.V. All rights reserved.