ISSN:
1089-7690
Source:
AIP Digital Archive
Topics:
Physics
,
Chemistry and Pharmacology
Notes:
Ab initio molecular orbital calculations have been performed on the NO2+⋅X complexes (X=H2O, N2, and CO2). Optimized geometries and vibrational frequencies, as well as computed total energies have been used to calculate standard enthalpies, entropies, and free energies for the complexing reactions, and ligand-switching reactions between the three molecular complexes. The results obtained have been compared with experimental values where available. The following thermodynamic values are recommended for the association reaction NO2++X→NO2+⋅X: ΔH298=−16.8, −4.7, and −7.9 kcal mol−1 and ΔS298=−23.1, −20.2, and −20.8 cal mol−1 K−1, for X=H2O, N2, CO2, respectively. Corresponding thermodynamic values for the ligand-switching reactions have also been calculated. Minimum energy geometries calculated for NO2+⋅H2O and NO2+⋅N2 are found to be in agreement with those obtained in previous theoretical studies. The NO2+⋅CO2 complex has been studied for the first time, and the minimum energy geometry has been shown to be planar and of C2v geometry. © 1997 American Institute of Physics.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1063/1.473266
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