Semiclassical transition state theory

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Semiclassical Transition State Theory (SCTST) [1] [2] is an efficient chemical rate theory, which aims to calculate accurate rate constants of chemical reactions, including nuclear quantum effects such as tunnelling, from ab initio quantum chemistry. [3] [4] [5] The method makes use of the semiclassical WKB wavefunction, Bohr-sommerfeld theory and vibrational perturbation theory to derive an analytical relation for the probability of a particle transmitting through a potential barrier at some energy, E. It was first developed by Bill Miller and coworkers in the 1970's, and has been further developed to allow for application to larger systems [6] and using more accurate potentials. [7]

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References

  1. Burd, Timothy A.H.; Shan, Xiao; Clary, David C. (2018-02-01). "Tunnelling and the kinetic isotope effect in CH3+CH4→CH4+CH3: An application of semiclassical transition state theory". Chemical Physics Letters. 693: 88–94. doi:10.1016/j.cplett.2018.01.002. ISSN   0009-2614.
  2. Miller, William H.; Hernandez, Rigoberto; Handy, Nicholas C.; Jayatilaka, Dylan; Willetts, Andrew (1990-08-24). "Ab initio calculation of anharmonic constants for a transition state, with application to semiclassical transition state tunneling probabilities". Chemical Physics Letters. 172 (1): 62–68. doi:10.1016/0009-2614(90)87217-F. ISSN   0009-2614.
  3. Greene, Samuel M.; Shan, Xiao; Clary, David C. (2016-02-28). "An investigation of one- versus two-dimensional semiclassical transition state theory for H atom abstraction and exchange reactions". The Journal of Chemical Physics. 144 (8): 084113. doi:10.1063/1.4942161. PMID   26931687.
  4. Nguyen, Thanh Lam; Barker, John R.; Stanton, John F. (2016-08-14). "Atmospheric Reaction Rate Constants and Kinetic Isotope Effects Computed Using the HEAT Protocol and Semi-Classical Transition State Theory". Advances in Atmospheric Chemistry. Advances in Atmospheric Chemistry. World Scientific. pp. 403–492. doi:10.1142/9789813147355_0006. ISBN   978-981-314-734-8.
  5. Miller, William H. (1975). "Semiclassical limit of quantum mechanical transition state theory for nonseparable systems". The Journal of Chemical Physics. 62 (5): 1899–1906. doi:10.1063/1.430676.
  6. Barker, John R.; Stanton, John F.; Nguyen, Thanh Lam (2010-10-20). "A practical implementation of semi-classical transition state theory for polyatomics". Chemical Physics Letters. 499 (1–3): 9–15. doi:10.1016/j.cplett.2010.09.015. ISSN   0009-2614.
  7. Wagner, Albert F. (2013-11-26). "Improved Multidimensional Semiclassical Tunneling Theory". The Journal of Physical Chemistry A. 117 (49): 13089–13100. doi:10.1021/jp409720s. PMID   24224758.