# fix drag command

## Syntax

fix ID group-ID drag x y z fmag delta

• ID, group-ID are documented in fix command
• drag = style name of this fix command
• x,y,z = coord to drag atoms towards
• fmag = magnitude of force to apply to each atom (force units)
• delta = cutoff distance inside of which force is not applied (distance units)

## Examples

fix center small-molecule drag 0.0 10.0 0.0 5.0 2.0


## Description

Apply a force to each atom in a group to drag it towards the point (x,y,z). The magnitude of the force is specified by fmag. If an atom is closer than a distance delta to the point, then the force is not applied.

Any of the x,y,z values can be specified as NULL which means do not include that dimension in the distance calculation or force application.

This command can be used to steer one or more atoms to a new location in the simulation.

Restart, fix_modify, output, run start/stop, minimize info: