Computer Science NASC Seminar
The MaxFlux Functional: Derivation, Numerics, and Application to LJ-38
Maria Cameron, New York University
November 20, 2009
Warren Weaver Hall, Room 1302
251 Mercer Street
New York, NY, 10012-1110
Fall 2009 NASC Seminars Calendar
The overdamped Langevin equation is often used as a model in molecular
dynamics. At low temperatures, a system evolving according to such an SDE
spends most of the time near the potential minima and performs rare transitions between them.
A number of methods have been developed to study the most likely transition paths.
I will focus on one of them: the MaxFlux functional.
The MaxFlux functional has been around for almost thirty years but not widely used
because it is challenging to minimize. Its minimizer provides a path along
which the reactive flux is maximal at a given
finite temperature. I will show two ways to derive it in the framework of transition path theory:
the lower bound approach and the geometrical approach. I will present an efficient way to
minimize the MaxFlux functional numerically. I will demonstrate its application to the problem
of finding the most likely transition paths in the Lennard-Jones-38 cluster between the
face-centered-cubic and icosahedral structures.