Structural control of the excited-state dynamics of bis(dipyrrinato)zinc complexes: self-assembling chromophores for light-harvesting architectures.
The replacement of the phenyl rings at the 5,5'-positions of a bis(dipyrrinato)zinc complex with mesityl groups transforms the molecule from a very weak emitter that deactivates rapidly after photoexcitation (Phif = 0.006; tau approximately 90 ps) to a highly fluorescent chromophore with a long-lived singlet excited state (Phif = 0.36; tau approximately 3 ns). The results demonstrate that steric constraints on aryl-ring internal rotation dramatically alter the excited-state properties of 5,5'-substituted bis(dipyrrinato)metal complexes. The insights establish the foundation for tuning the photophysical properties of these chromophores for use in diverse photochemical applications.
Department of Chemistry, Washington University, St. Louis, Missouri 63130-4889, USA.
Igor V
IV
Sazanovich
Christine
C
Kirmaier
Eve
E
Hindin
Lianhe
L
Yu
David F
DF
Bocian
Jonathan S
JS
Lindsey
Dewey
D
Holten