A DFT investigation of dissociation of nitrous acid, transformation of its monomeric isomers, their dimeric isomers, and dimerization

Abstract

AbstractThe structure optimization of the monomeric isomers of the nitrous acid HONO, their cyclic dimers (HONO)2, and transition states of their transformations has been carried out using the density functional theory calculations at the B3LYP/6‐311++G(d,p) and B3LYP/aug‐cc‐pVQZ levels of theory. Three monomeric isomers (c, t, and z isomers) and six dimeric isomers (cc, ct, cz, tt, zz, and tz isomers) were found. Dissociation of the most stable of the HONO isomer (t isomer) was investigated and its rate constant was obtained at the UB3LYP/aug‐cc‐pVQZ level. Energetics, thermodynamic properties, rate, and equilibrium constants of the monomeric and dimeric isomerizations of the nitrous acid were obtained. Dimerization energies, enthalpies, and free energies of the dimeric isomers, (HONO)2 were also obtained. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2010