Charge recombination reactions in photoexcited C[sub 60]-amine complexes studied by picosecond pump probe spectroscopy

Journal Article · Wed Dec 15 00:00:00 EST 1993 · Journal of the American Chemical Society; (United States)

DOI:https://doi.org/10.1021/ja00078a010· OSTI ID:7302079

Ghosh, H N; Pal, H; Sapre, A V; Mittal, J P ^[1]

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1. Bhabha Atomic Research Centre, Bombay (India)

Photoexcitation of complexes between fullerence C[sub 60] and organic amines in benzene solutions is known to result in charge separation (CS) and subsequent charge recombination (CR) reactions, which lead to varying yields of fullerence triplet formation. Picosecond flash photolysis studies are carried out on C[sub 60]-diphenylamine (DPA), C[sub 60]-triethylamine (TEA), C[sub 60]-diazabicyclooctane (DABCO), and C[sub 60]-triphenylamine (TPA) systems to find out mechanistic details of the triplet formation on CR by inducing heavy atom and polarity effects by using suitable solvents. It is found that in the case of C[sub 60]-DPA, C[sub 60]-TEA, and C[sub 60]-DABCO systems proton transfer from the amine cation to the C[sub 60] anion in the ion pair state dominates, leading to poor triplet yields, which improve in heavy atom containing solvents. In TPA, proton transfer is not possible and hence fullerene triplet yields are high. Increase of solvent polarity for this system results in decreased C[sub 60] triplet yields with a consequent increase in the ion dissociation yield. A suitable reaction scheme is proposed to explain the results obtained. 34 refs., 5 figs., 2 tabs.

• OSTI ID: 7302079
• Journal Information: Journal of the American Chemical Society; (United States), Vol. 115:25; ISSN 0002-7863
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
COMPLEXES
PHOTOLYSIS
SPECTROSCOPY
AMINES
BENZENE
COMPILED DATA
FULLERENES
TRIPLETS
VISCOSITY
AROMATICS
CARBON
CHEMICAL REACTIONS
DATA
DECOMPOSITION
ELEMENTS
HYDROCARBONS
INFORMATION
MULTIPLETS
NONMETALS
NUMERICAL DATA
ORGANIC COMPOUNDS
PHOTOCHEMICAL REACTIONS
400201* - Chemical & Physicochemical Properties
400500 - Photochemistry
400102 - Chemical & Spectral Procedures