Effect of Delocalization and Rigidity in the Acceptor Ligand on MLCT Excited-State Decay.
In its most simple form, the energy gap law for excited-state nonradiative decay predicts a linear dependence of ln k(nr) on the ground- to excited-state energy gap, where k(nr) is the rate constant for nonradiative decay. At this level of approximation, the energy gap law has been successfully applied to nonradiative decay in a wide array of MLCT excited states of polypyridyl complexes of Re(I), Ru(II), and Os(II). This relationship also predicts a dependence of k(nr) on the structural characteristics of the acceptor ligand. We report here a brief survey of the literature which suggests that such effects exist and have their origin in the extent of delocalization of the excited electron in the ligand pi framework and on acceptor ligand rigidity.
Treadway
Joseph A.
JA
Department of Chemistry, The University of North Carolina, CB#3290, Chapel Hill, North Carolina 27599-3290, Faculty of Chemistry, Pontificia Universidad Catolica de Chile, Casilla 306, Buzon 521, Santiago, Chile, and Department of Molecular Sciences, James Cook University of North Queensland, Townsville, Queensland 4811, Australia.
Loeb
Barbara
B
Lopez
Rosa
R
Anderson
Peter A.
PA
Keene
F. Richard
FR
Meyer
Thomas J.
TJ