Applying the Accelerated Weight Histogram method to alchemical transformations
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.. image:: ../images/awh_fep.jpg
Alchemical transformations are regularly used to compute free energies of
solvation, binding and mutation. The end states of interest are connected by a
path using a coupling parameter lambda. The standard procedure is to run
multiple simulations, each at a fixed value of lambda, and use Bennettâ€™s
acceptance ratio to obtain the free energy difference. The Accelerated Weight
histogram method can be used for such calculations. In this approach lambda is
varied dynamically in a single simulation, and the free energy difference can
be obtained directly. This has been implemented in the GROMACS 2021 release
and provides a simple and flexible way to compute alchemical free energies and
can be trivially parallelized using multiple walkers (copies of the system).
The application of AWH for solvation free energy calculation is available as
on online GROMACS tuturial at: `https://tutorials.gromacs.org/
`_
**Reference**
M\. Lundborg, J. Lidmar and B Hess `doi:10.1063/5.0044352 `_
**Webinar**
`Applying the Accelerated Weight Histogram method to alchemical transformations `_