ISSN:
1089-7690
Source:
AIP Digital Archive
Topics:
Physics
,
Chemistry and Pharmacology
Notes:
Ab initio quantum mechanical methods have been applied to the complexes of the nitrate anion (conventional D3h NO−3 and Cs ONOO− forms) with the water molecule, namely, NO−3⋅H2O and ONOO−⋅H2O. Equilibrium geometries and vibrational frequencies for a number of energy minima on the ground state potential energy surface have been determined using analytic energy first and second derivative techniques. The highest level of theory employed is the self-consistent field method with a double-zeta plus polarization basis set. The minimum energy structure (lying ∼15 kcal/mol below separated NO−3 +H2O) incorporates two hydrogen bonds in C2v symmetry. This theoretical dissociation energy agrees well with experiment. A second, more conventional single-hydrogen-bond structure is predicted to lie 2.6 kcal/mol higher in energy. At the most reliable level of theory, no distinct minimum was found for the hydrogen bonded structure between HNO3 (nitric acid) and OH−. Several minima (high lying energetically) between ONOO− and H2O are characterized theoretically.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1063/1.459692
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