MaxKinEff: A Collision Theory-Based Approach for Analyzing Turnover Frequency and Turnover Number in Catalytic...

The efficiency of catalysts relies on comprehending the underlying kinetics that govern their performance. Under the steady-state regime, the "rate" is referred to as the turnover frequency, where the reaction rate is first order with respect to catalysts. Here, we introduce the Maximum Kinetic Efficiency (MaxKinEff) model, grounded in collision theory, to predict efficiency based on maximum turnover frequency, $$ and maximum turnover number, $$ . The model was applied to molecular water oxidation using twenty-six transition metal catalysts from the first (3d), second (4d), and third (5d) rows. A thorough investigation reveals that [Ru(pda)(Br-py)₂] (pda=1,10-phenanthroline-2,9-dicarboxylate; Py=pyridinophane) exhibits a notable $$ of 1176.87×10^-5 s^-1 due to its larger collision diameter (σ_RC) and lower activation energy (E_a). Importantly, the trend in the computed $$ values aligns with experimental TON, $$ validating the model's accuracy. For instance, [Cp^*Ir(κ²-N,O)NO₃] is identified by MaxKinEff as a standout performer, with the normalized maximum computed TON, $$ resembling the experimental TON, $$ =2000.