Premium
SOLVENT‐INDUCED ENHANCEMENT OF WEAKLY ALLOWED VIBRONIC TRANSITIONS OF AROMATIC HYDROCARBONS
Author(s) -
Mukhopadhyay A. K.,
Georghiou S.
Publication year - 1980
Publication title -
photochemistry and photobiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.818
H-Index - 131
eISSN - 1751-1097
pISSN - 0031-8655
DOI - 10.1111/j.1751-1097.1980.tb02560.x
Subject(s) - chemistry , naphthalene , solvent , pyrene , dipole , photochemistry , solvent effects , polar , absorption (acoustics) , transition dipole moment , computational chemistry , organic chemistry , materials science , physics , astronomy , composite material
— The enhancement of weakly allowed vibronic bands in the fluorescence and absorption spectra of 1,12‐benzoperylene, 1,2,3,4‐dibenzanthracene, naphthalene and 1‐methylnaphthalene has been observed in polar solvents at room temperature. No satisfactory correlation has been found between the extent of solvent effect and the solvent dielectric constant, dipole moment or the Kosower's Z ‐value. It is proposed that, as we previously found for pyrene, the enhancement is the result of complex formation between the hydrocarbons and the polar solvents which reduces the molecular symmetry and gives, in turn, rise to the intensification of weakly allowed vibronic transitions. The finding that the 2‐methyl, 1,3‐dimethyl and 1,6‐dimethyl derivatives of naphthalene, which have in inert solvents more strongly allowed transitions than naphthalene, do not show the solvent effect to any appreciable extent is consistent with this interpretation.