  Distributed point charge models (DCM) and their minimal variants (MDCM) have
been integrated with tools widely used for condensed-phase simulations,
including a virial-based barostat and a slow-growth algorithm for thermodynamic
integration. Minimal DCM is further developed with a systematic approach to
reduce fitting errors in the electrostatic interaction energy and a new
fragment-based approach offers considerable speedup of the MDCM fitting process
for larger molecules with increased numbers of off-centered charged sites.
Finally, polarizable (M)DCM is also introduced in the present work. The
developments are used in condensed-phase simulations of popular force fields
with commonly applied simulation conditions. (M)DCM equivalents for a range of
widely used water force fields and for fluorobenzene (PhF) are developed and
applied along with the original models to evaluate the impact of reformulating
the electrostatic term. Comparisons of the molecular electrostatic potential
(MEP), electrostatic interaction energies, and bulk properties from molecular
dynamics simulations for a range of models from simple TIP$n$P ($n = 3-5$) to
the polarizable, multipolar iAMOEBA models for water and an existing
quadrupolar model for PhF confirm that DCMs retain the accuracy of the original
models, providing a homogeneous, efficient, and generic point charge
alternative to a multipolar electrostatic model for force field development and
multilevel simulations.
