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examples:potentials:pair:3

Examples : Pair Potentials

Warning: This is an example potential. Please do NOT use it for any real simulations!

This is a simple pair potential that can be used in potfit. The analytic function used is a Lennard-Jones.

It makes use of the smooth cutoff feature.

Example_Pair_3
#F 0 3
#T PAIR
#I 0 0 0
#E

# Enable the smooth cutoff with _sc
type lj_sc
cutoff 6.0
epsilon 0.10    0.00    1.00
sigma   2.50    1.00    4.00
# One additional parameter for the smooth cutoff function
h       1.00    0.50    2.00

# Enable the smooth cutoff with _sc
type lj_sc
cutoff 6.0
epsilon 0.10    0.00    1.00
sigma   2.50    1.00    4.00
# One additional parameter for the smooth cutoff function
h       1.00    0.50    2.00

# No smooth cutoff
type lj
cutoff 6.0
epsilon 0.10    0.00    1.00
sigma   2.50    1.00    4.00

To enable the smooth cutoff for a potential, the string _sc has to be appended to the identifier, e.g. lj_sc. This increases the number of parameters for this potential by one. The cutoff parameter is added at the end of the parameter table and usually called h.

The smooth cutoff can be enabled for each potential individually.

makeapot

The example potential can be generated with the following makeapot command:

makeapot -n 2 -i pair -f 2*lj_sc lj