Absorption changes and kinetic behavior produced by excitation of PtII(TPP) and PtIV(TTP)Cl2 with 35-ps flashes at 355 and 532 nm are reported. (TPP is tetraphenylporphyrin; TTP is tetratolylporphyrin.) The transient difference spectrum obtained for the Pt(II) compound persists for >10 ns and is assigned to the lowestring triplet, 3T (π, π*). Similar results were found for PdII(TPP). On the other hand, the absorption changes obtained for the PtIV compound decay rapidly, with a time constant of 45 ± 10 ps. This transient behavior is ascribed to a low-lying ring-to-metal [a2u(π)dx2-y2] charge-transfer state predicted by theory.
All Science Journal Classification (ASJC) codes
- Colloid and Surface Chemistry