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pair_style soft command

Syntax:

pair_style soft cutoff 

Examples:

pair_style soft 2.5
pair_coeff * * 0.0 60.0
pair_coeff 1 1 0.0 60.0 3.0 

Description:

Style soft computes pairwise interactions with the formula

It is useful for pushing apart overlapping atoms, since it does not blow up as r goes to 0. A is a pre-factor that varies in time from the start to the end of the run. The run command documents how to make the ramping take place across multiple runs. Rc is the cutoff.

The following coefficients must be defined for each pair of atoms 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:

Astart and Astop are the values of the prefactor at the start and end of the next run. At intermediate times the value of A will be ramped between these 2 values. Note that before performing a 2nd run, you will want to adjust the values of Astart and Astop for all type pairs, or switch to a new pair style.

The last coefficient is optional. If not specified, the global soft cutoff is used.

Restrictions: none

Related commands:

pair_coeff

Default: none