Exploring the conformational dynamics of alanine dipeptide in solution
subjected to an external electric field: A nonequilibrium molecular dynamics
simulation
In this paper, we investigate the conformational dynamics of alanine
dipeptide under an external electric field by nonequilibrium molecular dynamics
simulation. We consider the case of a constant and of an oscillatory field. In
this context we propose a procedure to implement the temperature control, which
removes the irrelevant thermal effects of the field. For the constant field
different time-scales are identified in the conformational, dipole moment, and
orientational dynamics. Moreover, we prove that the solvent structure only
marginally changes when the external field is switched on. In the case of
oscillatory field, the conformational changes are shown to be as strong as in
the previous case, and non-trivial nonequilibrium circular paths in the
conformation space are revealed by calculating the integrated net probability
fluxes.Comment: 23 pages, 12 figure