Deformed transition-state theory: Deviation from Arrhenius behavior and application to bimolecular hydrogen transfer reaction rates in the tunneling regime.

摘要: A formulation is presented for the application of tools from quantum chemistry and transition-state theory to phenomenologically cover cases where reaction rates deviate Arrhenius law at low temperatures. parameter d introduced describe deviation systems reaching thermodynamic limit identified as linearizing coefficient in dependence inverse activation energy with temperature. Its physical meaning given when can be ascribed mechanical tunneling its value calculated explicitly. Here, a new derivation previously established relationship features barrier potential surface. The proposed variant transition state permits comparison experiments tests against alternative formulations. Prescriptions are provided implemented three hydrogen transfer reactions: CH4 + OH → CH3 + H2O, CH3Cl + OH CH2Cl + H2O H2 + CN H + HCN, widely investigated both experimentally theoretically. © 2016 Wiley Periodicals, Inc.