Measurement of the absorption cross sections of unstable CS based on the dynamic equilibrium of CS2 and CS in the photolysis of CS2

The absorption cross sections, as important spectroscopic data, can be used for the identification and quantitative measurement of components. However, in view that carbon monosulfide (CS) is unstable and highly reactive, it is difficult to measure the absorption cross sections of CS. Therefore, a method for measuring absorption cross sections of CS based on the dynamic equilibrium between carbon disulfide (CS2) and CS in the photolysis CS2 is proposed in the paper, and the absorption cross sections of CS are obtained for the first time. Firstly, the method for evaluating CS2 concentrations is introduced, and the calculation formula of CS2 concentrations is given. Secondly, CS2 is converted to CS by increasing the intensity of incident light. Factors affecting CS2 conversion efficiency, such as the flow rate of CS2 and the intensity of incident light, are studied. Next, according to the conversion relationship between CS2 and CS, the CS concentration has been obtained by measuring the change of CS2 concentration. Finally, the CS absorption cross sections of (0.29 +/- 0.01) x 10(-16) cm(2)/molecule and (2.15 +/- 0.04) x 10(-16) cm(2)/molecule are provided at wavelengths of 250.88 nm and 257.60 nm, respectively. (C) 2020 Published by Elsevier Ltd.