fix_modify AtC set reference_potential_energy command — LAMMPS documentation

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# fix_modify AtC set reference_potential_energy command

## Syntax

    fix_modify <AtC fixID> set reference_potential_energy [<value|filename>]

- AtC fixID = ID of fix atc instance

- set reference_potential_energy = name of the AtC sub-command

- value = optional user specified zero point for PE in native LAMMPS energy units

- filename = optional user specified string for file of nodal PE values to be read-in

## Examples

    fix_modify AtC set reference_potential_energy
    fix_modify AtC set reference_potential_energy -0.05
    fix_modify AtC set reference_potential_energy myPEvalues

## Description

Used to set various quantities for the post-processing algorithms. It sets the zero point for the potential energy density using the value provided for all nodes, or from the current configuration of the lattice if no value is provided, or values provided within the specified filename.

## Restrictions

Must be used with fix atc hardy or fix atc field.

## Related AtC commands

- fix_modify AtC command overview

## Default

Defaults to the LAMMPS zero point i.e. isolated atoms.