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### fix reax/c/bonds command

Syntax:

    fix ID group-ID reax/c/bonds Nevery Nrepeat Nfreq filename

- ID, group-ID are documented in fix command
- reax/c/bonds = style name of this command
- Nevery = output interval in timesteps
- Nrepeat = # of times to use input values for calculating averages
- Nfreq = calculate averages every this many timesteps
- filename = name of output file

Examples:

    fix 1 all reax/c/bonds 10 10 100 bonds.reaxc

Description:

Write out the bond information computed by the ReaxFF potential specified by pair_style reax/c. Bond order values are averaged and the bond information is written to filename on timesteps that are multiples of Nfreq, including timestep 0.

The Nevery, Nrepeat, and Nfreq arguments specify on what timesteps the input values will be used in order to contribute to the average. The final averaged quantities are generated on timesteps that are a multiple of Nfreq. The average is over Nrepeat quantities, computed in the preceding portion of the simulation every Nevery timesteps. Nfreq must be a multiple of Nevery and Nevery must be non-zero even if Nrepeat is 1. Also, the timesteps contributing to the average value cannot overlap, i.e. Nfreq > (Nrepeat-1)*Nevery is required.

For example, if Nevery=2, Nrepeat=6, and Nfreq=100, then values on timesteps 90,92,94,96,98,100 will be used to compute the final average on timestep 100. Similarly for timesteps 190,192,194,196,198,200 on timestep 200, etc.

The format of the output file should be self-explanatory. When using the same force field file with pair_style reax and pair_style reax/c, the following commands generate the same bond information:

    fix 1 all reax/bonds N bonds.reax
    fix 1 all reax/c/bonds 1 1 N bonds.reaxc

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

No information about this fix is written to binary restart files. None of the fix_modify options are relevant to this fix. No global or per-atom quantities are stored by this fix for access by various output commands. No parameter of this fix can be used with the start/stop keywords of the run command. This fix is not invoked during energy minimization.

Restrictions:

The fix reax/c/bonds requires that the pair_style reax/c be invoked. This fix is part of the USER-REAXC package. It is only enabled if LAMMPS was built with that package. See the Making LAMMPS section for more info.

Related commands:

pair_style reax/c, fix reax/bonds

Default: none