Semiclassical transition state theory explained

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]

Notes and References

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