Abstract: | AbstractModel complexes [MoVIO2(S2C2Me2)SMe]? (A, derived from the X-ray crystal structure of native sulfite oxidase (SO)) and [MoVIO2(mnt)2]2? (B, coordination mode similar to the active site of selenate reductase (SeR)) were computed at the COSMO-B3LYP/SDDp//B3LYP/Lanl2DZ(p) energy level of Density Functional Theory in order to study their behavior in oxidation of selenite (SeIV) and sulfite (SIV) to selenate (SeVI) and sulfate (SVI), respectively. For the oxidation of sulfite, computational model A, which resembles the SO active site, is clearly the best choice (lowest barrier, minor exothermicity). For the reduction of selenate, a smaller activation is computed for model A; however, the reaction is less exothermic with model B, which resembles the SeR active site. |