Author/Authors :
Sergei N. and Kruglik، نويسنده , , Sergie G. and Ermolenkov، نويسنده , , Vladimir V. and Shvedko، نويسنده , , Alexander G. and Orlovich، نويسنده , , Valentine A. and Galievsky، نويسنده , , Victor A. and Chirvony، نويسنده , , Vladimir S. and Otto، نويسنده , , Cees and Turpin، نويسنده , , Pierre-Yves، نويسنده ,
Abstract :
A photoinduced complex between Cu(TMpy-P4) and water molecules, reversibly axially coordinated to the central metal, was observed in picosecond transient absorption and nanosecond resonance Raman experiments. This complex is rapidly created (τ1 = 15 ± 5 ps) in the excited triplet (π, π∗) state of Cu-porphyrin, and the subsequent relaxation is proposed to proceed via two parallel pathways. One is fast and efficient (⩾ 90% of molecules), and presumably involves a (π, d) charge-transfer state. The second pathway is slow (τ2 ⪢ 1 ns), has a low quantum yield (⩽ 10%) and involves the excited (d, d) state which is responsible for transient Raman features at ≈ 1553 cm−1 (ν2∗) and ≈ 1347 cm−1 (ν4∗), and for low-intensity long-lived transient absorption features.
