Journal of porphyrins and phthalocyanines vol:5 issue:1 pages:33-43
Sharp line emission spectra of the silicon phthalocyanine complex ((n-C6H13)(3)SiO)(2)SiPc at low temperatures are resolved in multiple sites, and the vibronic fine structure of single-site emissions is identified. DFT methods are used to calculate the complete set of normal modes of the Cl2SiPc analogue. Geometry optimization of the excited state further yields the Franck-Condon and Jahn-Teller distortions in the emitting state. These results are combined to obtain theoretical Huang-Rhys factors for the active modes, which compare favourably with the experimental spectrum. The dominant satellites are a 675 cm(-1) mode, which is identified as a totally symmetric bending of the four pyrrole rings, and a 1552 cm(-1) mode, which is assigned to an antisymmetric stretching of the aza-nitrogens with tetragonal b(1g) symmetry. Copyright (C) 2001 John Wiley & Sons, Ltd.