Solvent and temperature dependence of intramolecular energy transfer in the complex ((dmb) sub 2 Ru(b-b)Ru(dmb)(CN) sub 2 ) sup 2+
- Tulane Univ., New Orleans, LA (USA)
The complex ((dmb){sub 2}Ru(b-b)Ru(dmb)(CN){sub 2}){sup 2+}, 1, was prepared (dmb = 4,4{prime}-dimethyl-2,2{prime}-bipyridine and b-b = 1,4-bis(2-(4{prime}-methyl-2,2{prime}-bipyridyl-4-yl)ethyl)benzene), and the redox and photophysical properties of the complex were examined in several solvents. Luminescence is observed from the Ru {yields} dmb metal to ligand charge-transfer (MLCT) states of both the ((dmb){sub 2}Ru(b-b)) and ((b-b)Ru(dmb)(CN){sub 2}) chromophores. The lifetime of the higher energy ((dmb){sub 2}Ru(b-b)) center of 1 is less than 450 ns in each solvent studied at room temperature, indicating significant quenching of the complex. Excitation spectra of the ((b-b)Ru(dmb)(CN){sub 2}) emission of complex 1 indicate that energy transfer from the ((dmb){sub 2}Ru(b-b)) center is contributing to the emission. From the emission energy of the ((dmb){sub 2}Ru(b-b)) center and redox data, photoinduced electron-transfer quenching of the donor is shown to be endergonic. The energy-transfer process exhibits both solvent dependence and temperature dependence. The temperature dependence of the energy-transfer rate between 200 and 300 K indicates the existence of more than one energy-transfer path. The data are analyzed in terms of combined Coulombic and electron-exchange energy-transfer mechanisms.
- OSTI ID:
- 7109199
- Journal Information:
- Journal of Physical Chemistry; (USA), Vol. 93:23; ISSN 0022-3654
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
RUTHENIUM COMPLEXES
PHOTOCHEMISTRY
CYANIDES
ENERGY TRANSFER
EXPERIMENTAL DATA
MEASURING INSTRUMENTS
MEASURING METHODS
REDOX REACTIONS
SOLVENT PROPERTIES
CHEMICAL REACTIONS
CHEMISTRY
COMPLEXES
DATA
INFORMATION
NUMERICAL DATA
TRANSITION ELEMENT COMPLEXES
360000* - Materials
360100 - Metals & Alloys
360104 - Metals & Alloys- Physical Properties