Excited-state equilibration over 30 A in a platinum(II) quinolinolate-bridge-platinum(II) porphyrin complex.

Abstract

Long-range triplet excited-state equilibration occurs over a nanometric distance between platinum(II) 8-quinolinolate (3Ptq2 = 1.87 eV) and platinum(II) tetraphenylporphyrin (3PtTPP = 1.89 eV). The equilibrium is mediated by a fluorene-thiophene-fluorene bridge (3FTF = 1.92 eV) and is characterized by a double-exponential decay (tau1 = 39 +/- 4 ps; tau2 = 351 +/- 15 ps) that suggests the participation of three separate excited states: 3Ptq2, 3FTF, and 3PtTPP, respectively. Numerical simulation of the dual equilibrium allowed for estimation of the individual rate constants for each of the reversible steps (kET = 3.9 x 10(9)-4.1 x 10(10) s(-1)). As a result of rapid triplet-state equilibration, almost 50% of the excited-state energy is directed from the PtTPP chromophore toward Ptq2, in spite of a small endothermic barrier (0.03 eV).

Cite this paper

@article{Montes2007ExcitedstateEO, title={Excited-state equilibration over 30 A in a platinum(II) quinolinolate-bridge-platinum(II) porphyrin complex.}, author={Victor A. Montes and Michael A. J. Rodgers and Pavel Anzenbacher}, journal={Inorganic chemistry}, year={2007}, volume={46 25}, pages={10464-6} }