Where do I determine the various coefficients required to conduct simulations under the reaxff engine of lammps.
I have a data file written with atom_style full, but I do not have any values for the above coefficients.
Is it acceptable to use previously determined coefficients from other force fields such as CHARMM or OPLS-AA
You should first read the documentation in LAMMPS:
https://docs.lammps.org/pair_reaxff.html
Which explains where to find some parameters distributed with LAMMPS:
"LAMMPS provides several different versions of ffield.reax in its potentials dir, each called potentials/ffield.reax.label. These are documented in potentials/README.reax. The default ffield.reax contains parameterizations for the following elements: C, H, O, N."
And where to ask for more parameters:
"We do not distribute a wide variety of ReaxFF force field files with LAMMPS. Adri van Duin’s group at PSU is the central repository for this kind of data as they are continuously deriving and updating parameterizations for different classes of materials. You can submit a contact request at the Materials Computation Center (MCC) website https://www.mri.psu.edu/materials-computation-center/connect-mcc, describing the material(s) you are interested in modeling with ReaxFF. They can tell you what is currently available or what it would take to create a suitable ReaxFF parameterization."
Then you should read the literature cited for the theory:
(Chenoweth_2008) Chenoweth, van Duin and Goddard, Journal of Physical Chemistry A, 112, 1040-1053 (2008).
(Aktulga) Aktulga, Fogarty, Pandit, Grama, Parallel Computing, 38, 245-259 (2012).
(Liu) L. Liu, Y. Liu, S. V. Zybin, H. Sun and W. A. Goddard, Journal of Physical Chemistry A, 115, 11016-11022 (2011).
- Badges
- Science topic