SEMINAR @ SISSA, SBP, dr. D. Branduardi - March 1, at 14.30 hrs.

[Barbara Corzani]

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STATISTICAL AND BIOLOGICAL PHYSICS SEMINAR
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Dr. Davide Branduardi

(Max Planck Institute for Biophysics . Frankfurt am Main)

 

Title:

"Metadynamics with flexible hills shape"

 

Thu March 1, 2012 @ 02.30 p.m.

 

SISSA - First floor - room 132
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ABSTRACT:

 

Metadynamics is a well known method for free energy calculations which has
been successfully applied to many problems related with overcoming free
energy barriers larger than KbT. Since this method relies on the addition of
repulsive multidimensional Gaussian potentials, is it mandatory to choose
their widths and orientation in each dimension. These widths are a measure
of the resolution of the expected free energy while the Gaussian orientation
is a measure of the linear dependence among different variables. Both
parameters are generally kept constant during the simulations (with some
exceptions).

Here I will show that it is possible to introduce two simple algorithms for
calculating hills widths and orientation on the fly by choosing only one
parameter, despite the dimensionality of the calculation. By taking
advantage of the welltempered metadynamics formulation, the correct estimate
of the free energy is easily retrieved. I will show numerical example by
using alanine dipeptide in vacuum.