fix_modify AtC time_integration command — LAMMPS documentation

\(\renewcommand{\AA}{\text{Å}}\)

# fix_modify AtC time_integration command

## Syntax

    fix_modify <AtC fixID> time_integration <descriptor>

- AtC fixID = ID of fix atc instance

- time_integration = name of the AtC sub-command

- descriptor = gear or fractional_step or verlet

## Examples

    fix_modify AtC time_integration fractional_step

## Description

Command to select the thermal or momentum time integration.

Options for thermal time integration:

gear

  atomic velocity update with second order Verlet, nodal temperature update with third or fourth order Gear, thermostats based on controlling power

fractional_step

  atomic velocity update with second order Verlet, mixed nodal temperature update, 3/4 Gear for continuum and 2 Verlet for atomic contributions, thermostats based on controlling discrete energy changes

Options for momentum time integration:

verlet

  atomic velocity update with second order Verlet, nodal temperature update with second order Verlet, kinetostats based on controlling force

fractional_step

  atomic velocity update with second order Verlet, mixed nodal momentum update, second order Verlet for continuum and exact second order Verlet for atomic contributions, kinetostats based on controlling discrete momentum changes

gear

  atomic velocity update with second order Verlet, nodal temperature update with third or fourth order Gear, kinetostats based on controlling power.

## Restrictions

None.

## Related AtC commands

- fix_modify AtC command overview

## Default

None.