title: Tuning J-aggregates of tetra(p-hydroxyphenyl)porphyrin by the headgroups of ionic surfactants in acidic nonionic micellar solution.
abstract: J-aggregates of the diacid form of tetra(p-hydroxyphenyl)porphyrin (THPP) were found to be stable in nonionic micellar solution in the presence of trace ionic surfactant with an oxyacid headgroup. The excitation energy of exciton coupling depends systematically on the headgroups of the ionic surfactant, by which strong and weak coupling can be accomplished in the J-aggregates. The J-aggregates have two strong exciton bands corresponding to the B- and Q-bands of the protonated monomers. The total fluorescence of THPP is quenched through aggregate formation. A strong and sharply peaked resonance light-scattering signal that suggests a delocalized excitonic state was observed just slightly to the red of the absorption maximum of the J-aggregates. The overall resonance Raman intensities appeared to be stronger in the aggregates than in the monomers. In the kinetics of aggregation induced by sodium dodecyl sulfate (SDS), no characteristics of autocatalyzed reactions were observed, and there was only a logarithmic phase that lasted only several seconds.
authors.affiliation: State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan 430072, P.R. China.
authors.forename: Xiwen
authors.initials: X
authors.lastname: Li
authors.forename: Zhongliang
authors.initials: Z
authors.lastname: Zheng
authors.forename: Mingyue
authors.initials: M
authors.lastname: Han
authors.forename: Zhangping
authors.initials: Z
authors.lastname: Chen
authors.forename: Guolin
authors.initials: G
authors.lastname: Zou
mesh_terms: D000143:Acids / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D007477:Ions / Q000737:chemistry*; D007700:Kinetics; D008823:Micelles; D015394:Molecular Structure; D011166:Porphyrins / Q000737:chemistry*; D012967:Sodium Dodecyl Sulfate; D012996:Solutions; D013053:Spectrophotometry; D013501:Surface-Active Agents / Q000737:chemistry*; D013696:Temperature
chemical_list: D000143:Acids; D007477:Ions; D008823:Micelles; D011166:Porphyrins; D012996:Solutions; D013501:Surface-Active Agents; D012967:Sodium Dodecyl Sulfate; C051232:5,10,15,20-tetra(4-hydroxyphenyl)porphyrin