This repository contains an example driver built using the MolSSI Driver Interface (MDI). It implements a Nudged Elastic Band (NEB) calculation using engines running independent versions of LAMMPS [1]. We modeled our NEB Driver after the LAMMPS neb command, to provide a baseline for testing. This driver uses n independent replicas to perform an NEB operation. For each replica, and instance of LAMMPS is run to perform geometry optimizations. Each replica (instance of LAMMPS) requires a LAMMPS input and data file, distributed evenly accross the transition path to correctly operate. Provided with the Driver are a set of LAMMPS files to run the included test script.
This Driver requires LAMMPS, installed through the MDI fork and the MDI Driver. With both codes installed and this Driver downloaded and compiled, there are only a few steps needed to run the tests provided with the Driver.
First, edit the LAMMPS and MDI_NEB_DRIVER files located within the NEB_Driver/tests/locations folder. Edit the file paths to point to the executable of LAMMPS and the compiled driver binary.
Then, simply run the testing.sh scrpt in NEB_Driver/tests/NEB.
The script has the following command line interface:
testing.sh num_engines spring_force_constant energy_threshold force_threshold
num_engines: the number of engines (replicas) to be used with the driver.spring_force_constant: the constant used when determining the spring forces. (see [2] and [3] for a detailed description of the algorithm.)energy_threshold: the threshold to check if the energies have converged.force_threshold: the threshold to check if the forces have converged.
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