Crystallography and AM1 and INDO/S calculations on electronic ground and excited singlet states of 2-[p-(dimethylamino)phenyl]-3,3-dimethyl-3H-indole: solvent effects on the absorption and fluorescence spectra

1991 ◽  
Vol 95 (24) ◽  
pp. 9764-9772 ◽  
Author(s):  
M. LaChapelle ◽  
M. Belletete ◽  
M. Poulin ◽  
N. Godbout ◽  
F. LeGrand ◽  
...  
Keyword(s):  
Solvent Effects ◽  
Fluorescence Spectra ◽  
Absorption And Fluorescence Spectra ◽  
Excited Singlet ◽  
Singlet States ◽  
Excited Singlet States ◽  
Electronic Ground

Analytic energy derivative methods for excited singlet states of the same symmetry as the electronic ground state

1985 ◽  
Vol 83 (3) ◽  
pp. 1162-1167 ◽  
Author(s):  
George Fitzgerald ◽  
Henry F. Schaefer
Keyword(s):  
Ground State ◽  
Electronic Ground State ◽  
Excited Singlet ◽  
Singlet States ◽  
Excited Singlet States ◽  
Electronic Ground

Solvent Effects on the Nonradiative Relaxation Processes of the Lowest Excited Singlet States of Meso-substituted Bromoanthracenes

1983 ◽  
Vol 56 (6) ◽  
pp. 1851-1852 ◽  
Author(s):  
Kumao Hamanoue ◽  
Toshiharu Hidaka ◽  
Toshihiro Nakayama ◽  
Hiroshi Teranishi ◽  
Minoru Sumitani ◽  
...  
Keyword(s):  
Solvent Effects ◽  
Relaxation Processes ◽  
Nonradiative Relaxation ◽  
Excited Singlet ◽  
Singlet States ◽  
Excited Singlet States

scholarly journals The Ugi four-component reaction as a concise modular synthetic tool for photo-induced electron transfer donor-anthraquinone dyads

2014 ◽  
Vol 10 ◽  
pp. 1006-1016 ◽  
Author(s):  
Sarah Bay ◽  
Gamall Makhloufi ◽  
Christoph Janiak ◽  
Thomas J J Müller
Keyword(s):  
Electron Transfer ◽  
Excited Singlet ◽  
Gibbs Energies ◽  
Singlet States ◽  
Vis Spectroscopy ◽  
Donor Acceptor ◽  
Photo Induced Electron Transfer ◽  
Excited Singlet States ◽  
A Charge ◽  
Electronic Ground

Phenothiazinyl and carbazolyl-donor moieties can be covalently coupled to an anthraquinone acceptor unit through an Ugi four-component reaction in a rapid, highly convergent fashion and with moderate to good yields. These novel donor–acceptor dyads are electronically decoupled in the electronic ground state according to UV–vis spectroscopy and cyclic voltammetry. However, in the excited state the inherent donor luminescence is efficiently quenched. Previously performed femtosecond spectroscopic measurements account for a rapid exergonic depopulation of the excited singlet states into a charge-separated state. Calculations of the Gibbs energy of photo-induced electron transfer from readily available UV–vis spectroscopic and cyclovoltammetric data applying the Weller approximation enables a quick evaluation of these novel donor–acceptor dyads. In addition, the X-ray structure of a phenothiazinyl–anthraquinone dyad supports short donor–acceptor distances by an intramolecular π-stacking conformation, an important assumption also implied in the calculations of the Gibbs energies according to the Weller approximation.

Der Konzentrationsumschlag der Fluoreszenz aromatischer Kohlenwasserstoffe in mizell-kolloidaler Lösung

1964 ◽  
Vol 19 (1) ◽  
pp. 38-41 ◽  
Author(s):  
Th. Förster ◽  
B. Selinger
Keyword(s):  
Aqueous Solution ◽  
Fluorescence Spectra ◽  
Excited Singlet ◽  
Concentration Effects ◽  
Dimer Formation ◽  
Singlet States ◽  
Low Concentrations ◽  
Excited Singlet States ◽  
Methyl Naphthalene ◽  
Monomer Fluorescence

Concentration effects in fluorescence spectra, resulting from transient dimer formation in excited singlet states, have been studied in the presence of a detergent in aqueous solution. 2-methyl-naphthalene and pyrene have been used as fluorescers, and cetyl-dimethyl-benzylammonium-chloride as the detergent. The intensity ratio of dimer to monomer fluorescence components has been measured for dilution of the fluorescer alone and also of fluorescer and detergent. The results show that with 2-methyl-naphthalene transient dimer formation depends on the fluorescer concentration within the micelles. With pyrene, where dimer formation occurs at very low concentrations, it seems to depend on the number of single fluorescer molecules per micelle.

Sign in / Sign up

Export Citation Format

Share Document