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fix wall/lj126 command

Syntax:

fix ID group-ID wall/lj126 style coord epsilon sigma cutoff 

Examples:

fix wallhi all wall/lj126 xhi 10.0 1.0 1.0 1.12 

Description:

Bound the simulation domain with a Lennard-Jones wall that encloses the atoms. The energy E of a wall-particle interactions is given by the 12-6 potential

where r is the distance from the particle to the wall coord, and epsilon and sigma are the usual LJ parameters. Rc is the cutoff value specified in the command. This interaction provides a harder, more repulsive interaction with the wall than the softer 9-3 potential provided by the fix wall/lj93 command.

The wall potential is shifted so that the energy of a wall-particle interaction is 0.0 at the cutoff distance.

This fix makes a contribution to the potential energy of the system that can be included in thermodynamic output of potential energy using the fix_modify energy option. The contribution can also be printed by itself via the keyword f_fix-ID in the thermo_style custom command.

The forces due to this fix are also imposed during an energy minimization, invoked by the minimize command. If you want that energy to be included in the total potential energy of the system (the quantity being minimized), you must enable the fix_modify energy option for this fix.

Restrictions: none

Related commands:

fix wall/reflect, fix wall/lj93

Default: none