Comparison of quantum mechanical and empirical potential energy surfaces and computed rate coefficients for N2 dissociation

Richard L. Jaffe, David W. Schwenke, Maninder Grover, Paolo Valentini, Thomas E. Schwartzentruber, Simone Venturi, Marco Panesi

Research output: Chapter in Book/Report/Conference proceedingConference contribution


Comparisons are made between potential energy surfaces (PES) for N2 + N and N2 + N2 collisions and between rate coefficients for N2 dissociation that were computed using the quasiclassical trajectory method (QCT) on these PESs. For N2 + N we compare the Laganà’s empirical LEPS surface with one from NASA Ames Research Center based on ab initio quantum chemistry calculations. For N2 + N2 we compare two ab initio PESs (from NASA Ames and from the University of Minnesota). These use different methods for computing the ground state electronic energy for N4, but give similar results. Thermal N2 dissociation rate coefficients, for the 10,000K-30,000K temperature range, have been computed using each PES and the results are in excellent agreement. Quasi-stationary state (QSS) rate coefficients using both PESs have been computed at these temperatures using the Direct Molecular Simulation of Schwartzentruber and coworkers. The QSS rate coefficients are up to a factor of 5 lower than the thermal ones and the thermal and QSS values bracket the results of shock-tube experiments. We conclude that the combination of ab initio quantum chemistry PESs and QCT calculations provides an attractive approach for the determination of accurate high-temperature rate coefficients for use in aerothermodynamics modeling.

Original languageEnglish (US)
Title of host publication54th AIAA Aerospace Sciences Meeting
PublisherAmerican Institute of Aeronautics and Astronautics Inc, AIAA
ISBN (Print)9781624103933
StatePublished - 2016
Event54th AIAA Aerospace Sciences Meeting, 2016 - San Diego, United States
Duration: Jan 4 2016Jan 8 2016

Publication series

Name54th AIAA Aerospace Sciences Meeting


Other54th AIAA Aerospace Sciences Meeting, 2016
Country/TerritoryUnited States
CitySan Diego

ASJC Scopus subject areas

  • Aerospace Engineering


Dive into the research topics of 'Comparison of quantum mechanical and empirical potential energy surfaces and computed rate coefficients for N2 dissociation'. Together they form a unique fingerprint.

Cite this