Excited State Properties of Rh2(O2CCH3)4: Solution Photochemistry and Photoinitiated DNA Cleavage

摘要: Abstract The photophysical properties of Rh2(O2CCH3)4(L)2 (L = CH3OH, THF tetra-hydrofuran, PPh3 triphenylphosphine, py pyridine) were explored upon excitation with visible light. All the complexes exhibit a long-lived transient absorption signal (τ 3.5–5.0 μs) assigned as an electronic excited state each molecule. An optical transition at −760 nm is observed in spectra transients, whose position relatively independent axial ligand. No emission from THF, PPh3, py) systems was room temperature or 77 K, but energy transfer Rh2(O2CCH3)4(PPh3)2 to tetracene and perylene takes place form 3ππ∗ acceptor. Electron ∗Rh2(O2CCH3)4(PPh3)2 dimethyl viologen (MV2+) chloro-p-benzoquinone (Cl-BQ) quenching rate constants (kq) 8.0 × 106 M−1s−1 1.2 methanol, respectively. A kq value 2 108 measured for s...