| Title: | Thermochemistry of methyl and ethyl nitro, RNO2, and nitrite, RONO, organic compounds
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| Authors: | Asatryan R., Bozzelli J.W. and Simmie J.M., 2008 |
| Abstract: | Computational quantum theory is employed to determine the thermochemical properties of n-alkyl nitro and nitrite compounds: methyl and ethyl nitrites, CH3ONO and C2H5ONO, plus nitromethane and nitroethane, CH3NO2 and C2H5NO2, at 298.15 K using multilevel G3, CBS-QB3, and CBS-APNO composite methods employing both atomization and isodesmic reaction analysis. Structures and enthalpies of the corresponding aci-tautomers are also determined. The enthalpies of formation for the most stable conformers of methyl and ethyl nitrites at 298 K are determined to be −15.64 ± 0.10 kcal mol-1 (−65.44 ± 0.42 kJ mol-1) and −23.58 ± 0.12 kcal mol-1 (−98.32 ± 0.58 kJ mol-1), respectively. ΔfHo(298 K) of nitroalkanes are correspondingly evaluated at −17.67 ± 0.27 kcal mol-1 (−74.1 ± 1.12 kJ mol-1) and −25.06 ± 0.07 kcal mol-1 (−121.2 ± 0.29 kJ mol-1) for CH3NO2 and C2H5NO2. Enthalpies of formation for the aci-tautomers are calculated as −3.45 ± 0.44 kcal mol-1 (−14.43 ± 0.11 kJ mol-1) for aci-nitromethane and −14.25 ± 0.44 kcal mol-1 (−59.95 ± 1.84 kJ mol-1) for the aci-nitroethane isomers, respectively. Data are evaluated against experimental and computational values in the literature with recommendations. A set of thermal correction parameters to atomic (H, C, N, O) enthalpies at 0 K is developed, to enable a direct calculation of species enthalpy of formation at 298.15 K, using atomization reaction and computation outputs. |
| ICHEC Project: | BurnQuest: Towards a World Class Combustion Chemistry Centre |
| Publication: | Journal of Physical Chemistry A (2008) 112: 3172-3185 |
| URL: | http://dx.doi.org/10.1021/jp710960u |
| Status: | Published |
