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### pair_style peri/pmb command

Syntax:

    pair_style peri/pmb

Examples:

    pair_style peri/pmb
    pair_coeff * * 1.6863e22 0.0015001 0.0005 0.25

Description:

Style peri/pmb style implements the Peridynamic bond-based prototype microelastic brittle (PMB) model, which can be used to model materials at the mesoscopic or macroscopic scale. The canonical paper on Peridynamics is (Silling). The implementation of Peridynamics in LAMMPS is described in (Parks). Also see the PDLAMMPS user guide for more details about this particular potential and using it in LAMMPS.

The following coefficients must be defined for each pair of atom types via the pair_coeff command as in the examples above, or in the data file or restart files read by the read_data or read_restart commands, or by mixing as described below:

- c (energy/distance/volume^2 units)
- horizon (distance units)
- s00 (unitless)
- alpha (unitless)

C is the effectively a spring constant for Peridynamic bonds, the horizon is a cutoff distance for truncating interactions, and s00 and alpha are used as a bond breaking criteria. The units of c are such that c/distance = stiffness/volume^2, where stiffness is energy/distance^2 and volume is distance^3. See the users guide for more details.

Mixing, shift, table, tail correction, restart, rRESPA info:

This pair style does not support mixing. Thus, coefficients for all I,J pairs must be specified explicitly.

This pair style does not support the pair_modify shift option.

The pair_modify table and tail options are not relevant for this pair style.

This pair style writes its information to binary restart files, so pair_style and pair_coeff commands do not need to be specified in an input script that reads a restart file.

This pair style can only be used via the pair keyword of the run_style respa command. It does not support the inner, middle, outer keywords.

Restrictions:

The peri/pmb style is part of the "peri" package. It is only enabled if LAMMPS was built with that package. See the Making LAMMPS section for more info.

Related commands:

pair_coeff

Default: none

(Parks) Parks, Lehoucq, Plimpton, Silling, to appear in Comp Phys Comm, (2008).

(Silling) Silling, J Mech Phys Solids, 48, 175-209 (2000).