Spectral dependence of the efficiency of direct optical excitation of molecular oxygen in tetrachloromethane

Abstract

The spectral dependence of the efficiency of direct optical excitation of an oxygen molecule in tetrachloromethane using cw LED sources with different wavelengths and an optical parametric oscillator with single-shot output radiation (tuning range of 415–670 nm) has been studied by recording the phosphorescence of singlet oxygen at the O₂(¹Δ_g)–O₂(³Σ_g) transition (λ = 1270 nm). The results show that single-shot irradiation of tetrachloromethane in the short-wavelength spectral range leads to efficient quenching of singlet- oxygen phosphorescence by the products of photolytic decomposition of solvent.