Methyl Cation Affinities of Rare Gases and Nitrogen and the Heat of Formation of Diazomethane
The methyl cation affinities of the rare gases have been calculated at 0 K and 298 K by using coupled cluster theory including noniterative, quasi-perturbative triple excitations level with the new correlation-consistent basis sets for Xe up through aug-cc-pV5Z in some cases. In order to achieve near chemical accuracy ({+-} 1 kcal/mol) in the thermodynamic properties, we add to the estimated complete basis set valence binding energies based on frozen core coupled cluster theory energies two corrections: (1) a core/valence correction and (2) a scalar relativistic correction. Vibrational zero point energies were computed at the coupled cluster level of theory at the CCSD(T)/aug-cc-pVDZ level. The calculated rare gas methyl cation affinities (MCA) at 298 K are: MCA(He) = 1.7, MCA(Ne) = 2.5, MCA(Ar) = 16.9, MCA(Kr) = 25.5, and MCA(Xe) = 36.6 kcal/mol. Because of the importance of the MCA(N{sub 2}) in the experimental measurements of the MCA scale, we calculated a number of quantities associated with CH{sub 3}N{sub 2}{sup +} and CH{sub 2}N{sub 2}. The calculated values for diazomethane at 298 K are: {Delta}H{sub f}(CH{sub 2}N{sub 2}) = 65.3 kcal/mol, PA (CH{sub 2}N{sub 2}) = 211.9 kcal/mol, and MCA(N{sub 2}) = 43.2 kcal/mol.
- Research Organization:
- Pacific Northwest National Laboratory (PNNL), Richland, WA (US), Environmental Molecular Sciences Laboratory (EMSL)
- Sponsoring Organization:
- USDOE
- DOE Contract Number:
- AC05-76RL01830
- OSTI ID:
- 15016897
- Report Number(s):
- PNNL-SA-43952; 3565; KP1301030; TRN: US200516%%1047
- Journal Information:
- Journal of Physical Chemistry A, Vol. 109, Issue 18
- Country of Publication:
- United States
- Language:
- English
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