Perturbation of electronic states and energy relaxation dynamics in a series of phenylene bridged Zn^II porphyrin dimers

We have investigated the perturbed electronic states and energy relaxation dynamics of a series of phenylene bridged Zn^IIorphyrin dimers to reveal the effects of phenylene bridges by using computational and time-resolved spectroscopic methods. The electronic states of Zn^IIorphyrin dimers are largely perturbed by the interchromophore interactions that can be controlled by the phenylene bridges; linking position and number of phenyl rings. On the basis of our observations, we can gain further insight into the dipole-dipole interactions and through-bond/through-space electronic exchange interactions between the neighboring porphyrin moieties, which provides a firm basis for further understanding the modification of photophysical properties caused by the phenylene bridge in multiporphyrin assemblies as artificial light-harvesting apparatus.