LAMMPS (17 Feb 2022) # GCMC for CO2 molecular fluid, rigid/small dynamics # Rigid CO2 TraPPE model # [Potoff and J.I. Siepmann, Vapor-liquid equilibria of # mixtures containing alkanes, carbon dioxide and # nitrogen AIChE J., 47,1676-1682 (2001)]. # variables available on command line variable mu index -8.1 variable disp index 0.5 variable temp index 338.0 variable lbox index 10.0 variable spacing index 5.0 # global model settings units real atom_style full boundary p p p pair_style lj/cut/coul/long 14 pair_modify mix arithmetic tail yes kspace_style ewald 0.0001 bond_style harmonic angle_style harmonic # box, start molecules on simple cubic lattice lattice sc ${spacing} lattice sc 5.0 Lattice spacing in x,y,z = 5 5 5 region box block 0 ${lbox} 0 ${lbox} 0 ${lbox} units box region box block 0 10.0 0 ${lbox} 0 ${lbox} units box region box block 0 10.0 0 10.0 0 ${lbox} units box region box block 0 10.0 0 10.0 0 10.0 units box create_box 2 box bond/types 1 angle/types 1 extra/bond/per/atom 2 extra/angle/per/atom 1 extra/special/per/atom 2 Created orthogonal box = (0 0 0) to (10 10 10) 1 by 2 by 2 MPI processor grid molecule co2mol CO2.txt Read molecule template co2mol: 1 molecules 0 fragments 3 atoms with max type 2 2 bonds with max type 1 1 angles with max type 1 0 dihedrals with max type 0 0 impropers with max type 0 create_atoms 0 box mol co2mol 464563 units box Created 24 atoms using box units in orthogonal box = (0 0 0) to (10 10 10) create_atoms CPU = 0.002 seconds # rigid CO2 TraPPE model pair_coeff 1 1 0.053649 2.8 pair_coeff 2 2 0.156973 3.05 bond_coeff 1 0 1.16 angle_coeff 1 0 180 # masses mass 1 12.0107 mass 2 15.9994 # MD settings group co2 type 1 2 24 atoms in group co2 neighbor 2.0 bin neigh_modify every 1 delay 10 check yes velocity all create ${temp} 54654 velocity all create 338.0 54654 timestep 1.0 # rigid constraints with thermostat fix myrigid co2 rigid/small molecule mol co2mol create bodies CPU = 0.000 seconds 8 rigid bodies with 24 atoms 1.16 = max distance from body owner to body atom # dynamically update fix rigid/nvt/small temperature ndof fix_modify myrigid dynamic/dof yes # gcmc variable tfac equal 5.0/3.0 # (3 trans + 2 rot)/(3 trans) fix mygcmc co2 gcmc 100 100 0 0 54341 ${temp} ${mu} ${disp} mol co2mol tfac_insert ${tfac} group co2 rigid myrigid fix mygcmc co2 gcmc 100 100 0 0 54341 338.0 ${mu} ${disp} mol co2mol tfac_insert ${tfac} group co2 rigid myrigid fix mygcmc co2 gcmc 100 100 0 0 54341 338.0 -8.1 ${disp} mol co2mol tfac_insert ${tfac} group co2 rigid myrigid fix mygcmc co2 gcmc 100 100 0 0 54341 338.0 -8.1 0.5 mol co2mol tfac_insert ${tfac} group co2 rigid myrigid fix mygcmc co2 gcmc 100 100 0 0 54341 338.0 -8.1 0.5 mol co2mol tfac_insert 1.66666666666667 group co2 rigid myrigid # atom counts variable carbon atom "type==1" variable oxygen atom "type==2" group carbon dynamic co2 var carbon dynamic group carbon defined group oxygen dynamic co2 var oxygen dynamic group oxygen defined variable nC equal count(carbon) variable nO equal count(oxygen) # output variable tacc equal f_mygcmc[2]/(f_mygcmc[1]+0.1) variable iacc equal f_mygcmc[4]/(f_mygcmc[3]+0.1) variable dacc equal f_mygcmc[6]/(f_mygcmc[5]+0.1) variable racc equal f_mygcmc[8]/(f_mygcmc[7]+0.1) # dynamically update default temperature ndof compute_modify thermo_temp dynamic/dof yes thermo_style custom step temp press pe ke density atoms v_iacc v_dacc v_tacc v_racc v_nC v_nO thermo 1000 # run run 20000 Ewald initialization ... using 12-bit tables for long-range coulomb (src/kspace.cpp:340) G vector (1/distance) = 0.16463644 estimated absolute RMS force accuracy = 0.033206372 estimated relative force accuracy = 0.0001 KSpace vectors: actual max1d max3d = 16 2 62 kxmax kymax kzmax = 2 2 2 generated 1 of 1 mixed pair_coeff terms from arithmetic mixing rule WARNING: Fix gcmc using full_energy option (src/MC/fix_gcmc.cpp:486) 0 atoms in group FixGCMC:gcmc_exclusion_group:mygcmc 0 atoms in group FixGCMC:rotation_gas_atoms:mygcmc WARNING: Neighbor exclusions used with KSpace solver may give inconsistent Coulombic energies (src/neighbor.cpp:635) Neighbor list info ... update every 1 steps, delay 10 steps, check yes max neighbors/atom: 2000, page size: 100000 master list distance cutoff = 16 ghost atom cutoff = 16 binsize = 8, bins = 2 2 2 1 neighbor lists, perpetual/occasional/extra = 1 0 0 (1) pair lj/cut/coul/long, perpetual attributes: half, newton on pair build: half/bin/newton stencil: half/bin/3d bin: standard Per MPI rank memory allocation (min/avg/max) = 15.98 | 15.98 | 15.98 Mbytes Step Temp Press PotEng KinEng Density Atoms v_iacc v_dacc v_tacc v_racc v_nC v_nO 0 386.52184 23582.465 -3.2433417 14.209828 0.5846359 24 0 0 0 0 8 16 1000 384.36044 168.85423 -23.23758 19.858894 0.80387436 33 0.066251757 0.059749054 0 0 11 22 2000 259.20275 79.927114 -7.8419025 6.9537074 0.43847693 18 0.051929539 0.052057755 0 0 6 12 3000 302.33017 445.51546 -13.370306 12.616643 0.65771539 27 0.047267159 0.046725853 0 0 9 18 4000 311.19874 -941.64049 -29.224589 17.624862 0.87695385 36 0.054172258 0.052814245 0 0 12 24 5000 357.15913 -643.8797 -23.716174 18.453474 0.80387436 33 0.044110118 0.044289139 0 0 11 22 6000 343.81577 816.03183 -23.966196 17.764058 0.80387436 33 0.042107357 0.041553567 0 0 11 22 7000 360.66228 -396.06153 -12.261373 13.259144 0.5846359 24 0.046352562 0.047370093 0 0 8 16 8000 536.38773 97.164555 -1.3308134 6.3954798 0.21923846 9 0.088510977 0.090746839 0 0 3 6 9000 768.3631 251.53458 -0.87836731 5.3441371 0.14615898 6 0.11093712 0.11396968 0 0 2 4 10000 219.20608 -312.87929 -18.365974 9.1477634 0.65771539 27 0.117446 0.11875767 0 0 9 18 11000 380.32873 -455.7618 -19.955783 17.761107 0.73079488 30 0.11798452 0.11947738 0 0 10 20 12000 379.24355 197.4359 -2.1821544 4.521812 0.21923846 9 0.12913146 0.13205423 0 0 3 6 13000 396.07556 137.32879 -13.038496 14.561054 0.5846359 24 0.14552187 0.14709749 0 0 8 16 14000 324.11748 156.7682 -7.5905299 8.6951939 0.43847693 18 0.14458311 0.14598959 0 0 6 12 15000 355.07055 -171.07765 -14.067188 14.81757 0.65771539 27 0.14061899 0.14191715 0 0 9 18 16000 303.99764 -48.184319 -22.94389 15.70676 0.80387436 33 0.13709205 0.13778218 0 0 11 22 17000 233.8048 -12.817441 -10.840623 8.5954415 0.5846359 24 0.13670252 0.13812514 0 0 8 16 18000 288.74916 157.63378 -6.0604526 7.7463575 0.43847693 18 0.14212703 0.14298282 0 0 6 12 19000 285.23652 -41.79006 -1.0403841 1.9838837 0.14615898 6 0.1500458 0.15058244 0 0 2 4 20000 537.62536 77.091199 -3.9443433 9.0811682 0.29231795 12 0.15563619 0.1561609 0 0 4 8 Loop time of 8.33966 on 4 procs for 20000 steps with 12 atoms Performance: 207.203 ns/day, 0.116 hours/ns, 2398.178 timesteps/s 99.9% CPU use with 4 MPI tasks x no OpenMP threads MPI task timing breakdown: Section | min time | avg time | max time |%varavg| %total --------------------------------------------------------------- Pair | 0.23792 | 0.33196 | 0.40407 | 10.7 | 3.98 Bond | 0.0061255 | 0.0062467 | 0.0063458 | 0.1 | 0.07 Kspace | 0.1676 | 0.2404 | 0.33413 | 12.6 | 2.88 Neigh | 0.019046 | 0.019101 | 0.01916 | 0.0 | 0.23 Comm | 0.67736 | 0.68025 | 0.68266 | 0.3 | 8.16 Output | 0.00081757 | 0.00087737 | 0.0010462 | 0.0 | 0.01 Modify | 7.0053 | 7.0093 | 7.0134 | 0.1 | 84.05 Other | | 0.05152 | | | 0.62 Nlocal: 3 ave 5 max 0 min Histogram: 1 0 0 0 1 0 0 0 0 2 Nghost: 711 ave 750 max 671 min Histogram: 1 1 0 0 0 0 0 0 0 2 Neighs: 321.25 ave 568 max 0 min Histogram: 1 0 0 1 0 0 0 0 1 1 Total # of neighbors = 1285 Ave neighs/atom = 107.08333 Ave special neighs/atom = 2 Neighbor list builds = 20160 Dangerous builds = 0 Total wall time: 0:00:08