Quenching of Singlet Oxygen (1deltag) by Cobalt Complexes

Péter Baranyai, Sándor Németh and Tamás Vidóczy
Central Research Institute for Chemistry of the Hungarian Academy of Sciences


The quenching of singlet oxygen (1deltag) by cobalt(III)-bis-semibenzoquinone-diiminato complexes has been studied in different solvents by measuring the singlet oxygen phosphorescence signal in time-resolved experiments. The quenching is diffusion controlled, the reactive radius of the encounter pair has been estimated as 0.38nm, smaller than the radius of the complex itself, indicating that the singlet oxygen has to approach the central cobalt atom.