rPM6 Parameters for Manganese and Application to Transition State Search for Oxidation Reactions of Cyclohexene by Manganese(IV)-Oxo Species

<p>We report a fast, easy-to-handle, and accurate semiempirical quantum mechanical method to find a transition state (TS) for Mn-catalyzed oxidation reactions. Following our previous work, the reparameterization of PM6 (rPM6) for Mn is performed based on our training set. The spin-unrestricted calculations with the resultant parameter sets (UrPM6) successfully provide acceptable TS structures similar to the UDFT-optimized geometries at much lower computational cost. Our method will lead to substantial savings of computational time spent in the TS search for transition-metal-containing species.</p>