CHARMM Development Project Forums User Discussion & Questions Molecular Dynamics Flexible water model

Hi, what flexible water models are compatible with charmm/charmm36/charmm36m? I made 4 different lipid membrane input files in charmm-gui with tip3 water model in between, but the rigid models show the same dipole and dielectric constants for all systems. So I need to use a flexible water model. I am using Gromacs to run calculations. What are your suggestions? thank you.

The CHARMM36 force fields have all been developed for use with the additiveTIP3P model, with fixed atomic partial charges. Substitutions are not recommended without careful testing, esp. for the lipid force field. Most alternate water models are more expensive to use, and have not shown marked improvement for solute properties.

CHARMM has a polarizable Drude force field, which has been implemented in OpenMM and NAMD, but which Gromacs does not support.