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app_style relax command


app_style relax delta 


app_style relax 0.5 


This is an off-lattice application which treats sites as particles which interact through a pair potential and whose collective energy is relaxed via Metropolis Monte Carlo translational moves.

The energy of a particle I is as follows:

Ei = Sum_j phi(Rij) 

where Sum_j is a sum over all the neighbor of pariticle I within some cutoff distance, phi() is the potential energy function defined by the pair_style command, and Rij is the distance between particles I and J. The energy of the entire system is the sum of Ei over all particles. The pair_style command also defines the cutoff distance.

As explained on this page, this application is evolved by a Metroplis Monte Carlo (MMC) algorithm. You must thus define a sweeping method to be used with the application via the sweep command.

For solution by the MMC algorithm, once a particle is chosen, a translational move of the particle is made, by choosing a random location within a sphere of radius delta surrounding the particle. The energy of the particle before and after the move is calculated, to give dE = Efinal - Einitial. The move is accepted if R < min[1,exp(-dE/kT)], else it is rejected, where R is a uniform random number R between 0 and 1.

The following additional commands are defined by this application:

temperature set Monte Carlo temperature

Restrictions: none

Related commands:

Default: none