Transition State Theory

Rare events are widespread phenomena in Nature, such as protein folding, crystal nucleation and genetic switch flipping, only to mention few examples. All rare events share a common feature: they occur on timescales that are much longer compared to the shortest relevant timescale of the system, thus showing a clear separation of timescales. This wide disparity of timescales present serious computational challenges. One way to get around this problem is to focus on the dynamical bottleneck for the rare event: this is the main focus of the Transition State Theory (TST). TST was originally proposed by Wigner, Eyring, Evans and Polanyi in 1935 to understand how chemical reactions work and measure their reaction rate. Later on, Chandler and Anderson re-formulated TST with a more modern and computationally accessible language.

In my talk, I will review the Transition State Theory (TST) in its original version, introduce Chandler's approach for the TST and few issues related to the calculation of the transition rate.