Author/Authors :
Shuali، نويسنده , , Zohar and Berg، نويسنده , , Alexander and Levanon، نويسنده , , Haim and Vogel، نويسنده , , Emanuel and Brِring، نويسنده , , Martin and Sessler، نويسنده , , Jonathan L. and Fowler، نويسنده , , Chris and Weghorn، نويسنده , , Steven J.، نويسنده ,
Abstract :
The photoexcited triplet state of the two new porphyrin isomers, octaethylhemiporphycene (OEHPC) and octaethylcorrphycene (OECPC), embedded in isotropic (toluene) and an anisotropic liquid crystal matrices was studied by time-resolved electron paramagnetic resonance (EPR) spectroscopy in the temperature range of 150–300 K. The magnetic, kinetic and orientation parameters were determined and interpreted in terms of structure, symmetry and dynamic. Analysis of the results suggests that at T⩾250 K, the orientation and packing of the chromophores result from a discrete solid-like jumps mechanism, which is more efficient for OECPC. This difference is rationalized in terms of differences in the symmetry of the two chromophores.
