Excited quartet and doublet states in the complex of tetraphenylporphine zinc (II) and a nitroxide radical in solution: X- and W-band time-resolved EPR studies

The photoexcited quartet (Q1) and doublet (D1) states of the complex of tetra-phenyl-porphine zinc (II) and a nitroxide radical have been studied in toluene solution by X-(9.4 GHz) and W-band (94 GHz) time-resolved electron paramagnetic resonance spectroscopy. The spin-polarized signals of the Q1 and D1 states are observed and assigned by analysis of theg-values. Line broadening and spin polarization mechanisms in this system are discussed.