(no subject)

Dear LAMMPS Users,

I have been trying to calculate the diffusion coefficient of water in molecular dynamics simulation using the DRUDE FORCE FIELD. I tried to follow the instructions on the LAMMPS user manual for how to use the drude force field as also outlined in a 2015 publication “Journal of Chemical Information and Modeling 2016, 56, 1, 260-268”. I have been trying to do an NPT simulation followed by an NVT simulation with the Nose-Hoover thermostat. I get values for the diffusion coefficient of water which is an order of magnitude smaller ( 3.49e-06 cm^2/s). I have run simulations with other force fields such as SPC/E and TIP3P, the values I get are similar to what is published in the literature. I would appreciate it very much if someone can point out any issues with the lammps input script or the data which are attached.



in.water.swm4nh.12.5 (2.39 KB)

dat.water.swm4-ndp (435 KB)

I think you should send this Q to the Drude developers. See src/USER-DRUDE/README.
They could advise whether your input script looks OK, or whether there is
some other issue with using the Drude model for diffusion coeffs.