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### pair_style lj command

**Syntax:**

pair_style lj Ntypes cutoff

- lj = style name of this pair style
- Ntypes = # of particle types
- cutoff = global cutoff for pairwise interactions (distance units)

**Examples:**

pair_style lj 1 2.5
pair_style lj 3 3.0

**Description:**

The *lj/cut* style computes the standard 12/6 Lennard-Jones potential,
given by

Rc is the cutoff.

The following coefficients must be defined for each pair of particle
types via the pair_coeff command, or by mixing as
described below:

- epsilon (energy units)
- sigma (distance units)
- cutoff (distance units)

Note that sigma is defined in the LJ formula as the zero-crossing
distance for the potential, not as the energy minimum at 2^(1/6)
sigma.

The last coefficients is optional. If not specified, the global LJ
cutoff specified in the pair_style command is used.

**Mixing info**:

For atom type pairs I,J and I != J, the epsilon and sigma coefficients
and cutoff distance for all of the lj/cut pair styles can be mixed.
The style of mixing is *geometric*, which means that

epsilon_ij = sqrt(epsilon_i * epsilon_j)
sigma_ij = sqrt(sigma_i * sigma_j)

**Restrictions:** none

**Related commands:** none

**Default:** none