Stable configurations of neutral NO2(H2O)n complexes and [NO2(H2O)n]- anions corresponding to the local minima of the potential energy surfaces of the systems with n ≤ 50 were found in the unrestricted Hartree-Fock approximation with second-order corrections according to the Möller-Plesset perturbation theory. The calculations were performed using the 6-31G basis set augmented with polarization and diffuse functions on all nuclei and the technique of effective core potentials for describing water molecules of the external coordination sphere when n > 8. The special features of electron density distribution in the complex systems were analyzed. The effect of cavity contraction in the network of H-bonds around the NO2 fragment that accompanied the localization of an excess electron by the system was revealed. The vertical and adiabatic electron affinity for the complexes NO 2(H2O)n with n = 1-8 and 50 and the energies of vertical electron detachment from the anions were calculated. Analytic approximations to their dependences on the number of water molecules in the clusters were obtained. These dependences could be used to estimate the energy characteristics of extremely dilute solutions of NO2 and NO 2- in water.
|Number of pages||9|
|Journal||Russian Journal of Physical Chemistry A|
|Publication status||Published - Jan 2005|