Benjamin A. Ellingson

TL;DR: The algorithm and validation for OMEGA, a systematic, knowledge-based conformer generator, are presented and it is found to perform very well in reproducing the crystallographic conformations from both these data sets using two complementary metrics of success.

TL;DR: In this article, the rotational symmetry number for different molecular configurations and how to apply them to transition state theory is discussed. But special care is advised in the evaluation of symmetry numbers in the following situations: (i) reaction is symmetric, (ii) if reactants and/or transition states are chiral, (iii) if the reaction has multiple conformers for reactants or transition states and, (iv) if there is an internal rotation of part of the molecular system.

TL;DR: In this paper, the authors describe the application of variational transition state theory (VTST) to the calculation of chemical reaction rates, and present a review of the most important developments in this area.

TL;DR: Practical approximation schemes for calculating partition functions of torsional modes are tested against accurate quantum mechanical results for H(2)O( 2) and six isotopically substituted hydrogen peroxides and the effectiveness of these methods for the calculation of isotope effects is studied.

TL;DR: Rate constants for the OH + H2S --> H2O + HS reaction, which is important for both atmospheric chemistry and combustion, are calculated by direct dynamics with the M06-2X density functional using the MG3S basis set using the reference-potential Pitzer-Gwinn treatment of the torsional mode.