CCL: MC simulation of dense hard sphere system



 Sent to CCL by: "Joshua T Berryman" [josh.berryman[a]uni.lu]
 >>The problem I am facing is that most of the times new configurations are
 >>rejected because of overlapping spheres and acceptance I get is very
 low.
 >>What should I do for getter better acceptance, I tried very small
 >>displacements also.
 Yes, converging an HS system can be surprisingly expensive.  You have two
 choices, one is to optimize your code (see the book Allen and Tildesley,
 example code is on github:   https://github.com/Allen-Tildesley/examples ).
 Useful optimisations include: Cell system, Almarza barostat, automatic setting
 of stepsize.  Almarza barostat is particularly useful for generating a dense-
 packed system as the acceptance rate for volume changes does not vanish with
 an increasing number of particles.
 The second choice is to use an optimised existing code.  I would recommend
 dynamo: http://dynamomd.org/
 . Note that dynamo is EDMD, not MC. Speed is in
 my experience comparable or better, due to the large expense of random number
 generation in MC.
 Dr Josh Berryman
 Uni Luxembourg