Skip to main content
Article
Vibrational Energy Levels of the Simplest Criegee Intermediate (CH2OO) from Full-dimensional Lanczos, MCTDH, and MULTIMODE Calculations
Journal of Chemical Physics
  • Hua-Gen Yu
  • Steve Alexandre Ndengué
  • Jun Li
  • Richard Dawes, Missouri University of Science and Technology
  • Hua Guo
Abstract
Accurate vibrational energy levels of the simplest Criegee intermediate (CH2OO) were determined on a recently developed ab initio based nine-dimensional potential energy surface using three quantum mechanical methods. the first is the iterative Lanczos method using a conventional basis expansion with an exact Hamiltonian. the second and more efficient method is the multi-configurational time-dependent Hartree (MCTDH) method in which the potential energy surface is refit to conform to the sums-of-products requirement of MCTDH. Finally, the energy levels were computed with a vibrational self-consistent field/virtual configuration interaction method in MULTIMODE. the low-lying levels obtained from the three methods are found to be within a few wave numbers of each other, although some larger discrepancies exist at higher levels. the calculated vibrational levels are very well represented by an anharmonic effective Hamiltonian.
Department(s)
Chemistry
Research Center/Lab(s)
Center for High Performance Computing Research
Keywords and Phrases
  • Calculations,
  • Hamiltonians,
  • Molecular physics,
  • Potential energy,
  • Potential energy surfaces,
  • Quantum chemistry,
  • Quantum theory,
  • Vibrations (mechanical),
  • Configuration interaction method,
  • Criegee intermediates,
  • Effective Hamiltonian,
  • Iterative Lanczos method,
  • Multimode calculations,
  • Quantum mechanical method,
  • Self-consistent field,
  • Vibrational energy levels,
  • Iterative methods
Document Type
Article - Journal
Document Version
Final Version
File Type
text
Language(s)
English
Rights
© 2015 American Institute of Physics (AIP), All rights reserved.
Publication Date
8-1-2015
Citation Information
Hua-Gen Yu, Steve Alexandre Ndengué, Jun Li, Richard Dawes, et al.. "Vibrational Energy Levels of the Simplest Criegee Intermediate (CH2OO) from Full-dimensional Lanczos, MCTDH, and MULTIMODE Calculations" Journal of Chemical Physics Vol. 143 Iss. 8 (2015) ISSN: 0021-9606
Available at: http://works.bepress.com/richard_dawes/109/