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### bond_style hybrid command

Syntax:

    bond_style hybrid style1 style2 ...

- style1,style2 = list of one or more bond styles

Examples:

    bond_style hybrid harmonic fene
    bond_coeff 1 harmonic 80.0 1.2
    bond_coeff 2* fene 30.0 1.5 1.0 1.0

Description:

The hybrid style enables the use of multiple bond styles in one simulation. A bond style is assigned to each bond type. For example, bonds in a polymer flow (of bond type 1) could be computed with a fene potential and bonds in the wall boundary (of bond type 2) could be computed with a harmonic potential. The assignment of bond type to style is made via the bond_coeff command or in the data file.

In the bond_coeff command, the first coefficient sets the bond style and the remaining coefficients are those appropriate to that style. In the example above, the 2 bond_coeff commands would set bonds of bond type 1 to be computed with a harmonic potential with coefficients 80.0, 1.2 for K, r0. All other bond types (2-N) would be computed with a fene potential with coefficients 30.0, 1.5, 1.0, 1.0 for K, R0, epsilon, sigma.

A bond style of none can be specified as the 2nd argument to the bond_coeff command, if you desire to turn off certain bond types.

Restrictions:

This bond style can only be used if LAMMPS was built with the "molecular" package (which it is by default). See the Making LAMMPS section for more info on packages.

Unlike other bond styles, the hybrid bond style does not store bond coefficient info for individual sub-styles in a binary restart files. Thus when retarting a simulation from a restart file, you need to re-specify bond_coeff commands.

Related commands:

bond_coeff, delete_bonds

Default: none