Potential Energy Surfaces and Dynamics of High Energy Species

Abstract

Several papers on ionic liquids have been published or submitted as a result of this grant. The first set of papers used second order perturbation theory to study the geometries and substituent effects of the cations commonly employed in energetic ionic liquids. These are variously substituted triazolium, tertazolium, and pentazolium cations. The heats of formation of all species were predicted using G2 and G3 theory. It was consistently found that the most energetic substituent's are -CN and -N3. When one cation is combined with one anion, proton transfer almost always occurs with no intervening energy barrier, yielding a neutral pair. When two ion pairs are considered, conceptually similar to the face of a crystal, the ion separated species is predicted to be 6 kcal/mol lower in energy than the double proton transferred neutral species. These calculations were done using coupled cluster theory, but this level of theory is too expensive to study larger clusters. Therefore, we have turned to the fragment molecular orbital method, which can retain the accuracy of full electronic structure theory calculations, while greatly reducing the cost.

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Document Details

Document Type
Technical Report
Publication Date
Apr 13, 2009
Accession Number
ADA589687

Entities

People

  • Mark S. Gordon

Organizations

  • Iowa State University

Tags

DTIC Thesaurus Topics

  • Accuracy
  • Chemical Compounds
  • Chemistry
  • Computational Chemistry
  • Computational Chemistry Methods
  • Decomposition
  • Dynamics
  • Electronic Structure Methods
  • Electronic Structure Theory
  • Electrons
  • Energy
  • First Principles Calculations
  • Heat Of Activation
  • High Energy
  • Ionic Liquids
  • Perturbation Theory
  • Potential Energy

Readers

  • Quantum Chemistry
  • Systems Analysis and Design

Technology Areas

  • Microelectronics
  • Space
  • Space - Hall-Effect Thruster