Quantum yield and rate constant of the singlet 1Δ g oxygen luminescence in an aqueous medium in the presence of nanoscale inhomogeneities

The quantum yields and lifetimes of photosensitized luminescence of the 1Δ g state of singlet oxygen in an aquatic media with a controlled concentration of dielectric anisotropy centers (polyethylene glycol) have been measured using the methods of laser fluorometry. It is established that the quantum yield and the rate constant (k r ) of the a 1Δ g → X 3Σ - luminescence of 1O2 increase as the polymer concentration increases. The effect is analyzed within a general approach involving a relationship between kr and dielectric properties of the medium and is explained by the increased density of photon states and the local field factor in the space around O2(а 1Δ g ).