Intrinsic and environmental effects on the kinetic and thermodynamics of linkage isomerization in nitritopentaamminecobalt(III) complex

In this paper we present a theoretical study of the linkage isomerization i n [Co(NH3)(5)ONO](2+). In particular, we have used for our analysis a hybri d density functional/Hartree-Fock method for the electronic computations (t he so-called B3LYP), while a recent version of the polarizable continuum mo del has been considered to model solute-solvent interactions. A particular effort has been devoted to understand the kinetics of the reaction and to a ssess the nature of the transition state. Our results show that this reacti on is only marginally exothermic in the gas phase, while solvent significan tly shifts the equilibrium toward the nitro isomer. We have also identified the transition state of the reaction, which can be described as a heptacoo rdinate structure with the NO2 group in eta (2) coordination.