Charge-transfer complexes of metal dithiolenes. IX. Photoinduced electron transfer within metal dithiolene-viologen ion pairs studied by flash photolysis

1992 ◽  
Vol 96 (25) ◽  
pp. 10323-10326 ◽  
Author(s):  
Horst Kisch ◽  
Walter Duemler ◽  
Claudio Chiorboli ◽  
Franco Scandola ◽  
Josef Salbeck ◽  
...  
Keyword(s):  
Electron Transfer ◽  
Charge Transfer ◽  
Photoinduced Electron Transfer ◽  
Flash Photolysis ◽  
Ion Pairs ◽  
Charge Transfer Complexes ◽  
Metal Dithiolenes

Charge-transfer ion pairs. Structure and photoinduced electron transfer of carbonylmetalate salts

1989 ◽  
Vol 111 (13) ◽  
pp. 4669-4683 ◽  
Author(s):  
T. M. Bockman ◽  
Jay K. Kochi
Keyword(s):  
Electron Transfer ◽  
Charge Transfer ◽  
Photoinduced Electron Transfer ◽  
Ion Pairs

Charge transfer emissive singlet excited states and photoinduced electron transfer properties in the diarylideneacetone compounds (RCHCH)2CO; R = phenyl, 1- and 2-naphthyl, 3-(N-ethylcarbazoyl), and 4-(C5H5)Fe(C5H4C6H4CHCH(CO)CHCHC6H5)

1990 ◽  
Vol 68 (12) ◽  
pp. 2278-2288 ◽  
Author(s):  
Pierre D. Harvey ◽  
Liangbing Gan ◽  
Christiane Aubry
Keyword(s):  
Electron Transfer ◽  
Excited State ◽  
Charge Transfer ◽  
Excited States ◽  
Photoinduced Electron Transfer ◽  
Flash Photolysis ◽  
Reduction Process ◽  
Transfer Reactions ◽  
Electron Transfer Reactions ◽  
Electron Reduction

Four diarylideneacetone compounds ((RCHCH)2CO, where the aryl groups are phenyl (dba), 1-naphthyl (1-dNapha), 2-naphthyl (2-dNapha), and 3-(N-ethylcarbazoyl) (dNECa)), and 4-(C5H5)Fe(C5H4C6H4CHCH(CO)CHCH(C6H5) (dba-Fc) have been prepared and characterized. The compounds are found to be fluorescent and photochemically and reversibly electrochemically active. The lowest-energy absorption bands for the diarylideneacetones are assigned to a charge transfer (CT) electronic transition, except for dba-Fc, in which a ferrocenyl ligand field transition assignment is made. The 77 K CT absorption and fluorescence bands are vibrationally structured (vibrational spacings = 1260–1360 cm−1). While the fluorescence decay at 293 K is monoexponential, the excited state fluorescence lifetimes (τF) for the 77 K samples exhibit double exponential decays, the short component being 0.38–0.64 ns and the long one 3.5–10.9 ns. The photophysical results are interpreted in terms of excited state deactivation processes dominated by radiationless pathways that are associated with the presence of fluorescent species with different geometries. Only the dNECa compound is found to be fluorescent in solution at 298 K [Formula: see text]. Cyclic voltammetry and coulometry measurements suggest that a reversible one-electron reduction process and an irreversible higher potential one-electron reduction process take place in the −1 to −2 V vs. SSCE range. In addition, dba-Fc also exhibits an electrochemically reversible one-electron oxidation wave at 0.52 V vs. SSCE centered at the ferrocenyl group. These results together with the spectroscopic electronic data have permitted evaluation of the reduction potentials of the lowest singlet (CT excited states (E1−/*);they range from 1.4 to 2.2 V vs. SSCE, with dba being the strongest photooxidizing agent and dNECa the weakest. Photoinduced intermolecular electron transfer reactions have been investigated by steady state fluorescence techniques and picosecond flash photolysis spectroscopy for dNECa and dba, respectively. The bimolecular deactivation rate constants, kq, for the reductive photoinduced electron transfer reactions of dNECa with diphenylamine (DPA) (kq = (2.65 ± 0.25) × 107 M−1 s−1) and N, N, N′, N′-tetramethylphenylenediamine (TMPM) (kq = (1.38 ± 0.03) × 108 M−1 s−1) have been obtained in THF solutions at 293 K. No fluorescence quenching is observed when oxidative and energy transfer quenchers are used with dNECa. For the non-emissive dba compound at room temperature, picosecond flash photolysis experiments show that quenching of the broad dba transient band (~500 nm) does indeed occur between 5 and 10 ns. Keywords: dibenzylideneacetone, charge transfer, photoelectron transfer.

Photoinduced electron transfer and charge resonance band in ion-pair charge-transfer complexes of styrylpyridinium tetraphenylborate

1995 ◽  
Vol 71 (1-3) ◽  
pp. 2069-2070 ◽  
Author(s):  
T. Nagamura ◽  
H. Kawai ◽  
T. Ichihara ◽  
H. Sakaguchi
Keyword(s):  
Electron Transfer ◽  
Charge Transfer ◽  
Photoinduced Electron Transfer ◽  
Ion Pair ◽  
Charge Transfer Complexes ◽  
Resonance Band

scholarly journals Femtosecond excited state dynamics of stilbene–viologen complexes with a weakly pronounced charge transfer

2020 ◽  
Vol 19 (9) ◽  
pp. 1189-1200
Author(s):  
Mikhail V. Rusalov ◽  
Valery V. Volchkov ◽  
Vladimir L. Ivanov ◽  
Mikhail Ya. Melnikov ◽  
Fedor E. Gostev ◽  
...  
Keyword(s):  
Electron Transfer ◽  
Excited State ◽  
Charge Transfer ◽  
Photoinduced Electron Transfer ◽  
Charge Transfer Complexes ◽  
Excited State Dynamics

Charge transfer complexes between bis(18-crown-6)stilbene and viologen analogues. A femtosecond study of photoinduced electron transfer.

Charge-Transfer Complexes of Metal Dithiolenes, XXII. Bis(maleonitriledithiolato)oxomolybdate(IV) – Bipyridinium Ion Pairs

1996 ◽  
Vol 129 (1) ◽  
pp. 33-37 ◽  
Author(s):  
Brigitte Götz ◽  
Falk Knoch ◽  
Horst Kisch
Keyword(s):  
Charge Transfer ◽  
Ion Pairs ◽  
Charge Transfer Complexes ◽  
Metal Dithiolenes
Sign in / Sign up

Export Citation Format

Share Document