[Quenching of the luminescence of singlet molecular oxygen by complexes of porphyrins and highly-charged metal ions].
Quenching of singlet oxygen luminescence by the complexes of tetraphenylporphin with Fe3+, Mn3+, Sn4+, and Al3+, synthetic dimer of TTP (mu-oxo-bis-FeTPP) and by Fe3+-meso-porphyrin-IX-dimethylester has been investigated. Quenching obeys the Stern - Folmer equation. The rate constants of 1O2 quenching (Kq) by monomeric Fe-Porphyrins correspond to 1-1.5 X 10(9) M-1.s-1 and do not depend on axial ligands bound to the metal (Cl-, CH3COO-, CNS-, pyridine). Dimerization decreases Kq down to 4 X 10(7) M-1.s-1.Kq of the complexes with Mn, Sn, and Al are equal to 2.5X10(8), 2X10(6), 10(7) M-1.s-1 respectively. The data suggest that quenching by the monomeric Fe- and, probably, Mn-porphyrins is due to energy transfer from 1O2 to the eta-d levels of the quenchers.
D000535:Aluminum; D055598:Chemical Phenomena; D002621:Chemistry; D004735:Energy Transfer; D007501:Iron; D049449:Luminescence; D008345:Manganese; D008665:Metalloporphyrins; D010100:Oxygen; D014001:Tin
D008665:Metalloporphyrins; D008345:Manganese; D014001:Tin; D000535:Aluminum; D007501:Iron; D010100:Oxygen
Tushenie liuminestsentsii singletnogo molekuliarnogo kisloroda kompleksami porfirinov s vysokozariadnymi ionami metallov.