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Download file# Molecular Dynamics Using Nonvariational Polarizable Force Fields: Theory, Periodic Boundary Conditions Implementation, and Application to the Bond Capacity Model

journal contribution

posted on 2019-10-11, 14:03 authored by Pier Paolo Poier, Louis Lagardère, Jean-Philip Piquemal, Frank JensenWe
extend the framework for polarizable force fields to include
the case where the electrostatic multipoles are not determined by
a variational minimization of the electrostatic energy. Such models
formally require that the polarization response is calculated for
all possible geometrical perturbations in order to obtain the energy
gradient required for performing molecular dynamics simulations. By
making use of a Lagrange formalism, however, this computationally
demanding task can be replaced by solving a single equation similar
to that for determining the electrostatic variables themselves. Using
the recently proposed bond capacity model that describes molecular
polarization at the charge-only level, we show that the energy gradient
for nonvariational energy models with periodic boundary conditions
can be calculated with a computational effort similar to that for
variational polarization models. The possibility of separating the
equation for calculating the electrostatic variables from the energy
expression depending on these variables without a large computational
penalty provides flexibility in the design of new force fields.