LAMMPS WWW Site - LAMMPS Documentation - LAMMPS Mailing List Archives
[lammps-users] how to perform grand canonical Monte Carlo simulation for binary mixture by LAMMPS?
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

[lammps-users] how to perform grand canonical Monte Carlo simulation for binary mixture by LAMMPS?


From: chenwei@...7134...
Date: Tue, 26 Sep 2017 17:55:15 +0800 (GMT+08:00)

Dear LAMMPS users,


I try to perform grand canonical Monte Carlo simulation for binary mixture by LAMMPS.


I want a pure GCMC simulator.


Firstly, I test the program by the simulation of one component hard sphere fluid. The cutoff distance of LJ 12-6 potential is set equal to sigma, it is not a perfect hard sphere system, but the density of the system from the simulation is very close to the theoretical one.


However, there is a problem when I do the simulation for a binary hard-sphere mixture.  The densities predicted by the simulator are always far away from the confirmed theoretical ones.


The GCMC exchange is performed by these two commands in my script:


fix                1 O gcmc 1 1 1 1 29494 $T 3.982254 0.1 group O

fix                2 C gcmc 1 1 1 2 29494 $T 1.065682 0.1 group C

In addition, the density of the atoms handled by the second fix command is always close to zero. Here,  the density of group C is almost zero, but if I change the order of those two fix commands, then the density of group O is close to zero.


The LAMMPS Version is (6 Jul 2017).


Please find the full .in script and the .data file from the attachment.


Thank you very much,


Wei

 


Attachment: LJ_MC.in
Description: Binary data

Attachment: system.data
Description: Binary data