New insights in the hydrolysis mechanism of carbon disulfide (CS2): a density functional study

Density functional theory (DFT) is used to look into the two-step hydrolysis mechanism of CS 2 . Through optimizing the structure of reactants, intermediates, transition states, and products, it can be seen that the first step of CS 2 is that CS 2 reacts with H 2 O first to form COS intermediate and the second step is COS intermediate reacts with H 2 O to form H 2 S and CO 2 . Hydrogen migration is crucial to the mechanism of CS 2 hydrolysis. In the reaction’s first step, the rate-determining step in both the single C = S path and the double C = S path possesses a higher barrier of 199.9 kJ/mol; however, the 127.9 kJ/mol barrier in the double C = S path is lower than the 142.8 kJ/mol in the single C = S path. So the double C = S path is better. Similarly, the order of the barriers for the three paths in the second reaction is C = S path