The nitric oxide molecule (NO) shows relevant role in several physiological and physiopathological processes. Ruthenium amines coordination compounds are used as model systems for regulate the concentration of NO in the biological environment. One of the most important routes for promote the liberation of NO involves, for example, the substitution reaction: [Ru(NH3)3(L1)(L2)(NO)]2+ + H2O -- [Ru(NH3)3(L1)(L2)(H2O)]2+ + NO. Despite of its essential importance, the thermodynamic and kinetic mechanism behind of this process is a topic still not completely understood. This project will investigate this substitution reaction with L1 and L2 = NH3, H2O and CO, where also will be evaluate the influence of the nature and relative position of the ligands. The geometries will be optimized with the computational model BP86/def2TZVP with the ECP28MDF for the Ru atom. The polarization continuum model (PCM) will be used for mimic water (H2O) solvation around of the metal complexes. Besides, water molecules will be put around of the Ru-NO chemical bond for define the feasible thermodynamic reaction. Thus, the transition state (TS) will be obtained with the objective of performer the intrinsic reaction coordinate (IRC) method for calculate the energy profile along the reaction coordinate. From these results, will be used the activation strain model (ASM) that will allow the energy decomposition analysis of this chemical reaction. Complementary, the topological analysis of the reagents, transition state, and products will be performed from the method quantum theory of atoms in molecules (QTAIM). Therefore, these results will determine the kinetic mechanism of this chemical reaction. All the calculations will be performed from software Orca 4.0.1, Amsterdam Density Functional (ADF) and AIMAll Professional (Version 17.11.14).
News published in Agência FAPESP Newsletter about the scholarship: