Premium
QUANTIFICATION OF THE SOLVENT EFFECTS ON THE TRIPLET QUANTUM YIELD OF PSORALEN BY THE “LINEAR SOLVATION ENERGY RELATIONSHIP”
Author(s) -
Melo Teresa Sae,
Bazin Marc,
RonfardHaret JeanClaude,
Santus René
Publication year - 1993
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.1751-1097.1993.tb04897.x
Subject(s) - quantum yield , chemistry , solvation , solvent , polarity (international relations) , yield (engineering) , flash photolysis , solvent polarity , hexane , photochemistry , analytical chemistry (journal) , computational chemistry , thermodynamics , organic chemistry , reaction rate constant , physics , biochemistry , quantum mechanics , kinetics , fluorescence , cell
Triplet formation quantum yields (Φ τ ) of psoralen in a set of 17 pure solvents ranging from n ‐hexane to water and in dioxane: water mixtures were obtained by nanosecond laser flash photolysis. The triplet yield increases with solvent polarity. The extremum values are 0.009 and 0.545 in n ‐hexane and water, respectively. Good correlations of the experimental Φ τ values with empirical “polarity” scales (Dimroth/Reichardt's E T [30], Kamlet/Taft's solva‐tochromic parameters β, and α, and Swains acity/basity A S /B S ) were obtained: Ln(φ T ‐1 ‐ 1) = 8.86 ‐ 0.143E T (30) Ln(φ T ‐1 ‐ 1) = 4.40 ‐ 2.34 τ ‐ 1.70α Ln(φ T ‐1 ‐ 1) = 4.65 ‐ 3.72A s ‐ 1.12B s The results are discussed in terms of the sensitivity of psoralen triplet quantum yield to solvent polarity and hydrogen‐bonding abilities.