# Proton Transfer Reactions

Bifunctional catalysis of mutarotaion of tetramethyl glucose by 2-pyridinone

- Coordinated transfer of protons
- First reaction step in conversion of alpha to beta TMG
- Nonadiabatic process: changes in quantum state of proton during transfer

We are developing methods of studying the detailed kinetics of proton transfer reactions using a mixture of quantum and classical dynamics. These reactions are complicated due to a breakdown of the Born-Oppenheimer approximation, which leads to quantum transitions as the heavy nuclei move during the reaction.

We are approaching this problem along two fronts: The first involves using classical
transition state theory to describe the kinetics of the proton transfer reaction. Because
hydrogen-bonded systems are difficult to describe accurately, we have developed
Monte-Carlo methods which use classically motivated
importance functions to improve sampling from an *ab-initio*, DFT potential.
This method drastically reduces the correlation time in the simulation and allows good statistical data to be obtained. Quantum corrections
are also incorporated into the description using path-integral methods.

The second approach is to describe the kinetic process in detail by performing molecular dynamics simulations in which quantum transitions are allowed to occur. We have developed an approximate scheme for performing these simulations. The method has been tested on simple model systems like:

**Model Potentials**

The new method gives results superior to other current techniques and should be amenable to the calculation of rate constants for real proton transfer systems.

## Model Potentials

This page is maintained by

*jmschofi@chem.utoronto.ca*

Created September 15, 1997. Last updated September, 2016.