Coming Attractions in LAMMPS

The current version of LAMMPS incorporates nearly all the features from previous parallel MD codes developed at Sandia. These include earlier versions of LAMMPS itself, Warp and ParaDyn for metals, and GranFlow for granular materials.

These are new features we'd like to eventually add to LAMMPS. Some are being worked on; some haven't been implemented because of lack of time or interest; others are just a lot of work!

Monte Carlo bond-swapping for polymers

This was an option in the Fortran 90 LAMMPS. It needs to be implemented more broadly for the current LAMMPS, since bonds and angles are more general.

torsional shear boundary conditions and temperature calculation

This was an option in the Warp EAM/LJ code, but it hasn't been a priority to add to LAMMPS.

NPT with changing box shape (Parinello-Rahman)

LAMMPS supports triclinic (non-orthongal) simulation domains and NEMD simulations (dynamic box shape change), but the NPT integrator has not been enhanced to allow for shape changes due to off-diagonal pressure tensor components.

bond creation potentials

Bond breaking potentials exist in LAMMPS (e.g. bond_style quartic), but bond creation is harder, due to changes required in topology data structures.

long-range point-dipole solver

A point-dipole force field with a cutoff is in LAMMPS, and we have code for a version that includes the long-range damping terms, but the long-range dipole-dipole solver (Ewald or PPPM) still remains to be done, as well as NVT/NPT integrators.

charge equilibration

Aidan Thompson implemented charge equilibration in his parallel MD code GRASP. We are planning to add it to LAMMPS as well.

ReaxFF force field

Aidan Thompson implemented ReaxFF in his parallel MD code GRASP with collaboration from Bill Goddard's group at CalTech. We are planning to call it as a library from LAMMPS.