Highly Optimized Object-oriented Many-particle Dynamics -- Blue Edition
hoomd_script.pair Namespace Reference

Commands that create forces between pairs of particles. More...

## Classes

class  coeff
Defines pair coefficients. More...
class  nlist
Interface for controlling neighbor list parameters. More...
class  pair
Generic pair force. More...
class  lj
Lennard-Jones pair force. More...
class  gauss
Gaussian pair force. More...
class  slj
Shifted Lennard-Jones pair force. More...
class  yukawa
Yukawa pair force. More...
class  ewald
Ewald pair force. More...
class  cgcmm
CMM coarse-grain model pair force. More...
class  table
Tabulated pair force. More...
class  morse
Morse pair force. More...
class  dpd
NVT Integration via Dissipative Particle Dynamics pair force. More...
class  dpd_conservative
DPD Conservative pair force. More...
class  eam
EAM pair force. More...
class  dpdlj
NVT Integration via Dissipative Particle Dynamics pair force with a Lennard Jones conservative force. More...
class  force_shifted_lj
Force-shifted Lennard-Jones pair force. More...

## Detailed Description

Commands that create forces between pairs of particles.

Generally, pair forces are short range and are summed over all non-bonded particles within a certain cutoff radius of each particle. Any number of pair forces can be defined in a single simulation. The net force on each particle due to all types of pair forces is summed.

Pair forces require that parameters be set for each unique type pair. Coefficients are set through the aid of the coeff class. To set this coefficients, specify a pair force and save it in a variable

 my_force = pair.some_pair_force(arguments...)


Then the coefficients can be set using the saved variable.

 my_force.pair_coeff.set('A', 'A', epsilon=1.0, sigma=1.0)
my_force.pair_coeff.set('A', 'B', epsilon=1.0, sigma=2.0)
my_force.pair_coeff.set('B', 'B', epsilon=2.0, sigma=1.0)


This example set the parameters epsilon and sigma (which are used in pair.lj). Different pair forces require that different coefficients are set. Check the documentation of each to see the definition of the coefficients.