https://doi.org/10.1351/goldbook.R05176
The @[email protected] that a reaction occurs when two particles undergo a collision. If \(N_{\text{c}}\) is the number of collisions occurring in unit time, and \(N_{\text{r}}\) the number of reactions occurring in unit time: \(P_{\text{r}}=\frac{N_{\text{r}}}{N_{\text{c}}}\).