HNNH3, a new possible isomer of N2H4: An ab initio study

✍ Scribed by Fujiang Ding; Liangfu Zhang

• Publisher: John Wiley and Sons
• Year: 1997
• Tongue: English
• Weight: 141 KB
• Volume: 64
• Category: Article
• ISSN: 0020-7608
• DOI: 10.1002/(sici)1097-461x(1997)64:4<447::aid-qua6>3.0.co;2-w

✦ Synopsis

Ab initio studies applying the 3-21G, 6-31G, and 6-31G** basis sets and also including the MP2 correction were carried out on H NNH , HNNH , and the 2 2 3 transition state of the reaction H NNH HNNH . First, the geometries of molecules 2 2 3

were optimized using the theoretical methods mentioned in the restricted Hartree᎐Fock Ž . RHF scheme. The energies of the molecules corresponding to RHFr6-31G** geometries were subsequently calculated including electron-correlation effects at the level of the Ž . second-order Møller᎐Plesset MP2 perturbation theory. The vibrational frequencies, net charges, and dipole moments were obtained from the theoretical calculations. The results of our calculations indicate unambiguously that H NNH is thermodynamically more 2 2 stable than is HNNH . On the other hand, an isolated HNNH molecule once created 3 3 would be stable since barriers for its unimolecular isomerization and decomposition are relatively high. But HNNH is unlikely to be isolated in measurable amounts because of 3 bimolecular tautomerization. Nevertheless, HNNH can be considered as an intermediate 3 in chemical processes involving N H .