LAMMPS (27 Nov 2018)
  using 1 OpenMP thread(s) per MPI task
# GCMC for LJ simple fluid, no dynamics
# T = 2.0
# rho ~ 0.5
# p ~ 1.5
# mu_ex ~ 0.0
# comparable to Frenkel and Smit GCMC Case Study, Figure 5.8

# variables modifiable using -var command line switch

variable        mu index -1.25
variable        temp index 2.0
variable	disp index 1.0
variable        lbox index 5.0

# global model settings

units           lj
atom_style      atomic
pair_style      lj/cut 3.0
pair_modify	tail no # turn of to avoid triggering full_energy

# box

region		box block 0 ${lbox} 0 ${lbox} 0 ${lbox}
region		box block 0 5.0 0 ${lbox} 0 ${lbox}
region		box block 0 5.0 0 5.0 0 ${lbox}
region		box block 0 5.0 0 5.0 0 5.0
create_box	1 box
Created orthogonal box = (0 0 0) to (5 5 5)
  1 by 2 by 2 MPI processor grid

# lj parameters

pair_coeff	* * 1.0 1.0
mass		* 1.0

# we recommend setting up a dedicated group for gcmc

group		gcmcgroup type 1
0 atoms in group gcmcgroup

# gcmc

fix             mygcmc gcmcgroup gcmc 1 100 100 1 29494 ${temp} ${mu} ${disp}
fix             mygcmc gcmcgroup gcmc 1 100 100 1 29494 2.0 ${mu} ${disp}
fix             mygcmc gcmcgroup gcmc 1 100 100 1 29494 2.0 -1.25 ${disp}
fix             mygcmc gcmcgroup gcmc 1 100 100 1 29494 2.0 -1.25 1.0

# atom count

variable 	type1 atom "type==1"
group 		type1 dynamic gcmcgroup var type1
dynamic group type1 defined
variable        n1 equal count(type1)

# averaging

variable	rho equal density
variable	p equal press
variable	nugget equal 1.0e-8
variable        lambda equal 1.0
variable     	muex equal ${mu}-${temp}*ln(density*${lambda}+${nugget})
variable     	muex equal -1.25-${temp}*ln(density*${lambda}+${nugget})
variable     	muex equal -1.25-2.0*ln(density*${lambda}+${nugget})
variable     	muex equal -1.25-2.0*ln(density*1+${nugget})
variable     	muex equal -1.25-2.0*ln(density*1+1e-08)
fix 		ave all ave/time 10 100 1000 v_rho v_p v_muex v_n1 ave one file rho_vs_p.dat
variable	rhoav equal f_ave[1]
variable	pav equal f_ave[2]
variable	muexav equal f_ave[3]
variable	n1av equal f_ave[4]

# output

variable	tacc equal f_mygcmc[2]/(f_mygcmc[1]+${nugget})
variable	tacc equal f_mygcmc[2]/(f_mygcmc[1]+1e-08)
variable	iacc equal f_mygcmc[4]/(f_mygcmc[3]+${nugget})
variable	iacc equal f_mygcmc[4]/(f_mygcmc[3]+1e-08)
variable	dacc equal f_mygcmc[6]/(f_mygcmc[5]+${nugget})
variable	dacc equal f_mygcmc[6]/(f_mygcmc[5]+1e-08)
compute_modify  thermo_temp dynamic yes
thermo_style    custom step temp press pe ke density atoms v_iacc v_dacc v_tacc v_rhoav v_pav v_muexav v_n1av
thermo          1000

# run

run             10000
Neighbor list info ...
  update every 1 steps, delay 10 steps, check yes
  max neighbors/atom: 2000, page size: 100000
  master list distance cutoff = 3.3
  ghost atom cutoff = 3.3
  binsize = 1.65, bins = 4 4 4
  1 neighbor lists, perpetual/occasional/extra = 1 0 0
  (1) pair lj/cut, perpetual
      attributes: half, newton on
      pair build: half/bin/atomonly/newton
      stencil: half/bin/3d/newton
      bin: standard
Per MPI rank memory allocation (min/avg/max) = 0.4477 | 0.4477 | 0.4477 Mbytes
Step Temp Press PotEng KinEng Density Atoms v_iacc v_dacc v_tacc v_rhoav v_pav v_muexav v_n1av 
       0            0            0            0           -0            0        0            0            0            0            0            0            0            0 
    1000    2.4378552    1.9014939     -3.23439    3.6030066        0.544       68  0.073050445  0.070796636   0.11934255      0.52552    1.3006333   0.04152087        62.56 
    2000    1.9339159    1.0360287   -3.5001391    2.8594327         0.56       70  0.069588893  0.068587488   0.11319584        0.542    1.4012888 -0.020696665        64.56 
    3000    1.8891807    2.2857708   -3.3755633    2.7954769        0.592       74  0.068329031  0.067640916   0.11187803      0.53536    1.3380926 0.0062359288        64.21 
    4000    2.0436517    1.7600211   -3.4067452    3.0229014        0.576       72  0.067464211  0.067003868   0.11060324      0.54144    1.4484907 -0.016246603        64.75 
    5000    2.1512268    1.0811095   -3.2418366    3.1786785        0.536       67  0.066830654  0.066717982    0.1094094      0.54368    1.4962073 -0.025791643        65.04 
    6000     2.128931    1.5444487   -3.1904474    3.1450116        0.528       66  0.067479197  0.067193531    0.1104464      0.53112    1.4247377  0.019908014        63.01 
    7000    1.8194311   0.72981963   -3.6601329    2.6912418        0.576       72  0.068131849  0.067910074   0.11182024      0.51968    1.4517098  0.063444774        61.72 
    8000     1.947817   0.74570466   -3.0935809    2.8753489        0.504       63  0.068034071  0.067855883   0.11217045      0.53304    1.4924302  0.012298733        63.45 
    9000    1.8942389    1.3367401   -2.8925016    2.7962574        0.504       63  0.068117479  0.067943081   0.11236152        0.536    1.4091106 0.0011494886        63.73 
   10000    2.2092799   0.95517153   -2.9117781    3.2586879         0.48       60  0.068264792  0.068016591   0.11310789      0.52272    1.4774174  0.051284873        62.04 
Loop time of 26.0069 on 4 procs for 10000 steps with 60 atoms

Performance: 166109.741 tau/day, 384.513 timesteps/s
95.9% CPU use with 4 MPI tasks x 1 OpenMP threads

MPI task timing breakdown:
Section |  min time  |  avg time  |  max time  |%varavg| %total
---------------------------------------------------------------
Pair    | 0.10309    | 0.115      | 0.1225     |   2.2 |  0.44
Neigh   | 0.3907     | 0.40447    | 0.41957    |   1.7 |  1.56
Comm    | 0.44236    | 0.46678    | 0.49472    |   2.8 |  1.79
Output  | 0.0011411  | 0.0062903  | 0.0080109  |   3.7 |  0.02
Modify  | 25         | 25.002     | 25.005     |   0.0 | 96.14
Other   |            | 0.01231    |            |       |  0.05

Nlocal:    15 ave 16 max 14 min
Histogram: 2 0 0 0 0 0 0 0 0 2
Nghost:    437 ave 446 max 431 min
Histogram: 2 0 0 0 0 0 1 0 0 1
Neighs:    529 ave 595 max 437 min
Histogram: 1 0 0 0 1 0 0 0 0 2

Total # of neighbors = 2116
Ave neighs/atom = 35.2667
Neighbor list builds = 10000
Dangerous builds = 0
Total wall time: 0:00:26
