# espressopp.interaction.LennardJones93Wall¶

This class defines a Lennard-Jones 9-3 SingleParticlePotential in the direction x.

$V(r) = \epsilon \left( \left(\frac{\sigma}{r}\right)^9 - \left(\frac{\sigma}{r}\right)^3 \right)$

where $$r$$ is the distance from the lower or upper wall in the x direction. $$V(r)=0$$ after a distance sigmaCutoff.

The parameters have to be defined for every species present in the system with setParams and can be retrieved with getParams.

Example:

>>> LJ93 = espressopp.interaction.LennardJones93Wall()
>>> LJ93.setParams(0, 6., 1., wall_cutoff)
>>> SPLJ93 = espressopp.interaction.SingleParticleLennardJones93Wall(system, LJ93)

espressopp.interaction.LennardJones93Wall()
espressopp.interaction.LennardJones93Wall.getParams(type_var)
espressopp.interaction.LennardJones93Wall.setParams(type_var, epsilon, sigma, sigmaCutoff, r0)
espressopp.interaction.SingleParticleLennardJones93Wall(system, potential)
espressopp.interaction.SingleParticleLennardJones93Wall.setPotential(potential)
class espressopp.interaction.LennardJones93Wall.LennardJones93Wall