Rate constant of the HONO + HONO → H2O + NO + NO2 reaction from ab initio MO and TST calculations

A. M. Mebel, Ming-Chang Lin*, C. F. Melius

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

45 Scopus citations


Kinetics and mechanism for the bimolecular decomposition of HONO have been studied by ab initio molecular orbital (G2M) and transition-state theory calculations. The reaction can take place by the interaction of a cis and a trans isomer or two cis or two trans isomers, via four-, five-, and six-member ring transition states, with decreasing reaction barriers as the size of the ring increases. The lowest energy path with a 13.7 kcal/ mol barrier was found to occur by the six-member ring TS1 formed by the reaction of cis- and trans-HONO. A similar six-member ring TS (TS2) formed by two cis isomers has a barrier height of 15.1 kcal/mol, which is very close to the 5-ring TS formed by two trans isomers, 15.7 kcal/mol. The total rate constant computed with the ab initio MO results, including the three reaction channels mentioned above and an additional channel involving a five-member ring TS formed by a cis- and a trans isomer with a 17.7 kcal/mol barrier, can be represented by the three-parameter expression for the 300-5000 K temperature range: k = 5.8 × 10-25T3.64 exp(-6109/T) cm3/(molecule's), which includes the Boltzmann-averaged contribution of the cis isomer. The theoretical value was found to be considerably lower than the available experimental results (which are believed to have suffered from deleterious surface effects).

Original languageEnglish
Pages (from-to)1803-1807
Number of pages5
JournalJournal of Physical Chemistry A
Issue number10
StatePublished - 5 Mar 1998


Dive into the research topics of 'Rate constant of the HONO + HONO → H2O + NO + NO2 reaction from ab initio MO and TST calculations'. Together they form a unique fingerprint.

Cite this