LAMMPS (13 Oct 2016) # sample LAMMPS input script for diffusion of 2d LJ liquid # mean-squared displacement via compute msd # settings variable x equal 40 variable y equal 40 variable rho equal 0.6 variable t equal 1.0 variable rc equal 2.5 # problem setup units lj dimension 2 atom_style atomic neigh_modify delay 0 every 1 lattice sq2 ${rho} lattice sq2 0.6 Lattice spacing in x,y,z = 1.82574 1.82574 1.82574 region simbox block 0 $x 0 $y -0.1 0.1 region simbox block 0 40 0 $y -0.1 0.1 region simbox block 0 40 0 40 -0.1 0.1 create_box 1 simbox Created orthogonal box = (0 0 -0.182574) to (73.0297 73.0297 0.182574) 4 by 2 by 1 MPI processor grid create_atoms 1 box Created 3200 atoms pair_style lj/cut ${rc} pair_style lj/cut 2.5 pair_coeff * * 1 1 mass * 1.0 velocity all create $t 97287 velocity all create 1 97287 fix 1 all nve fix 2 all langevin $t $t 0.1 498094 fix 2 all langevin 1 $t 0.1 498094 fix 2 all langevin 1 1 0.1 498094 fix 3 all enforce2d # equilibration run thermo 1000 run 5000 Neighbor list info ... 1 neighbor list requests update every 1 steps, delay 0 steps, check yes max neighbors/atom: 2000, page size: 100000 master list distance cutoff = 2.8 ghost atom cutoff = 2.8 binsize = 1.4 -> bins = 53 53 1 Memory usage per processor = 2.478 Mbytes Step Temp E_pair E_mol TotEng Press 0 1 -1.56492 0 -0.5652325 -1.5346995 1000 0.97537833 -1.5723957 0 -0.5973222 0.92877783 2000 0.99008371 -1.5748206 0 -0.58504633 1.0809416 3000 1.0111412 -1.5848987 0 -0.57407352 1.0174297 4000 1.0055417 -1.5857581 0 -0.58053054 0.95647691 5000 0.97069905 -1.5851114 0 -0.61471567 0.90108287 Loop time of 0.554412 on 8 procs for 5000 steps with 3200 atoms Performance: 3896017.421 tau/day, 9018.559 timesteps/s 98.9% CPU use with 8 MPI tasks x no OpenMP threads MPI task timing breakdown: Section | min time | avg time | max time |%varavg| %total --------------------------------------------------------------- Pair | 0.23992 | 0.24608 | 0.25161 | 0.7 | 44.39 Neigh | 0.063106 | 0.064417 | 0.066279 | 0.4 | 11.62 Comm | 0.072465 | 0.085066 | 0.094837 | 2.3 | 15.34 Output | 0.00013208 | 0.00013691 | 0.00014591 | 0.0 | 0.02 Modify | 0.11441 | 0.11621 | 0.11769 | 0.3 | 20.96 Other | | 0.04251 | | | 7.67 Nlocal: 400 ave 406 max 394 min Histogram: 1 1 0 1 0 2 1 0 1 1 Nghost: 202.5 ave 212 max 191 min Histogram: 1 0 0 0 3 1 0 2 0 1 Neighs: 2800.88 ave 2903 max 2690 min Histogram: 1 1 0 0 1 2 1 0 1 1 Total # of neighbors = 22407 Ave neighs/atom = 7.00219 Neighbor list builds = 599 Dangerous builds = 0 unfix 2 # data gathering run reset_timestep 0 # factor of 4 in 2 variables is for 2d compute msd all msd com yes variable twopoint equal c_msd[4]/4/(step*dt+1.0e-6) fix 9 all vector 10 c_msd[4] variable fitslope equal slope(f_9)/4/(10*dt) thermo_style custom step temp c_msd[4] v_twopoint v_fitslope # only need to run for 10K steps to make a good 100-frame movie #dump 1 all custom 1 tmp.dump id type vx vy vz #dump 2 all image 100 image.*.jpg type type zoom 1.6 adiam 1.2 thermo 1000 run 100000 Memory usage per processor = 2.853 Mbytes Step Temp c_msd[4] v_twopoint v_fitslope 0 0.97069905 0 0 5e+20 1000 0.98138076 4.0484996 0.20242494 0.18046446 2000 0.97606079 9.2121392 0.23030346 0.2091528 3000 0.97924866 14.815034 0.24691721 0.22619184 4000 0.98568451 20.516817 0.25646019 0.23715506 5000 0.97551815 27.33922 0.27339219 0.24709999 6000 0.98482252 34.37734 0.28647782 0.25735178 7000 0.9672559 41.696689 0.29783348 0.26654059 8000 0.9836541 48.340277 0.30212673 0.27440308 9000 0.99087147 56.042692 0.31134828 0.28113047 10000 0.99663166 63.69663 0.31848314 0.28767921 11000 0.97776688 71.144109 0.32338231 0.29344527 12000 0.98246011 78.301774 0.32625739 0.29849471 13000 0.98788732 85.061923 0.32716124 0.3026655 14000 0.96872483 91.1658 0.32559214 0.30601023 15000 0.98955796 97.278388 0.32426129 0.3084275 16000 0.99855196 104.23997 0.3257499 0.31049883 17000 0.98600861 110.66055 0.3254722 0.31220348 18000 0.98696963 116.90111 0.32472531 0.31352676 19000 0.9881192 124.21305 0.32687644 0.31480062 20000 0.98527319 131.09874 0.32774685 0.31596198 21000 0.99015191 137.89263 0.32831579 0.31705324 22000 0.97972418 146.68982 0.33338595 0.31833889 23000 0.98911012 155.1264 0.33723129 0.31979515 24000 0.98810498 162.88634 0.33934653 0.32131187 25000 0.96961962 170.37907 0.34075814 0.32276215 26000 0.99118408 179.26511 0.34474059 0.32427111 27000 0.98515159 185.90764 0.3442734 0.32574529 28000 0.98951677 192.12183 0.34307469 0.32700292 29000 0.9832026 196.99457 0.33964581 0.32799023 30000 0.98449493 203.48475 0.33914124 0.3287171 31000 0.96585993 210.06193 0.33880956 0.32935775 32000 0.98758117 218.94174 0.34209646 0.33001591 33000 0.98875584 225.96489 0.34237104 0.33072947 34000 0.98007229 233.5792 0.34349882 0.3314385 35000 0.98415295 241.98148 0.34568783 0.33216634 36000 0.98101154 250.30876 0.34765106 0.33295272 37000 0.97606878 258.2127 0.34893608 0.33377673 38000 0.97220293 266.40464 0.35053242 0.33459273 39000 0.979783 272.8578 0.34981769 0.33539728 40000 0.98375673 279.87598 0.34984497 0.33609699 41000 0.97506523 288.07676 0.35131312 0.33677708 42000 0.97106749 296.11647 0.3525196 0.33751312 43000 0.97717259 304.46747 0.35403194 0.33823441 44000 0.98541435 312.57228 0.35519578 0.3389771 45000 0.97678287 321.82674 0.35758527 0.33973306 46000 0.98169719 329.78197 0.35845866 0.34051748 47000 0.99471466 337.11283 0.35863066 0.34127239 48000 0.98332437 346.0754 0.3604952 0.34202442 49000 0.98126947 356.11859 0.36338631 0.34282132 50000 0.98809751 365.65248 0.36565248 0.34368171 51000 0.95919516 373.91833 0.36658659 0.34454516 52000 0.98097913 381.26492 0.36660089 0.34538506 53000 0.97774072 388.81031 0.36680218 0.34618232 54000 0.99096915 395.56767 0.36626636 0.3469296 55000 0.97652739 401.72735 0.36520668 0.34760374 56000 0.99185306 407.28834 0.3636503 0.34819906 57000 0.96289342 414.75298 0.3638184 0.34871992 58000 0.97871716 424.69443 0.36611588 0.34927986 59000 0.98637393 433.14205 0.36706953 0.34986296 60000 0.98009845 438.14533 0.36512111 0.35040349 61000 0.99416712 446.08007 0.3656394 0.35088379 62000 0.97612483 450.90846 0.36363585 0.35132647 63000 0.97786531 455.36749 0.36140277 0.35167458 64000 0.99080668 458.04873 0.35785057 0.3519105 65000 0.97952497 461.31241 0.3548557 0.3520506 66000 0.98095955 463.91727 0.35145248 0.35207764 67000 0.98370788 468.93 0.34994776 0.35204043 68000 0.96931818 471.07765 0.34638063 0.35192685 69000 0.98512552 474.59146 0.34390685 0.35174053 70000 0.98065743 478.66071 0.3419005 0.35149002 71000 0.98971283 482.57357 0.33984054 0.35119434 72000 0.99890324 485.32018 0.3370279 0.35084345 73000 0.98649924 490.19497 0.33574998 0.35043722 74000 0.98723422 496.04991 0.33516886 0.35003351 75000 1.0025633 501.6313 0.33442087 0.34962094 76000 0.97859959 505.97813 0.33288035 0.34921013 77000 0.97973006 510.55334 0.33152814 0.3487692 78000 0.9903944 515.06966 0.33017286 0.34830833 79000 0.96847518 518.76483 0.32833217 0.3478214 80000 0.99171112 524.18127 0.32761329 0.34733349 81000 0.97202573 529.09959 0.32660468 0.3468315 82000 0.99368438 535.80271 0.32670897 0.34633058 83000 0.97932483 543.08233 0.32715803 0.34586259 84000 0.99078651 547.57861 0.32593965 0.34540839 85000 0.98973457 552.24581 0.32485048 0.34493584 86000 0.9835873 557.3493 0.32404029 0.34446152 87000 0.97180564 564.93434 0.32467491 0.34400358 88000 0.99743353 571.39837 0.32465817 0.3435667 89000 0.98993437 577.81703 0.32461631 0.3431411 90000 0.9926071 583.39378 0.32410765 0.342724 91000 0.98800458 591.08741 0.3247733 0.34232767 92000 0.98501879 596.10133 0.32396811 0.34193949 93000 0.98810082 604.02652 0.32474544 0.3415681 94000 0.97563748 609.43676 0.32416849 0.341209 95000 0.97283448 615.15754 0.32376713 0.34084828 96000 0.9883071 622.30912 0.32411933 0.34049871 97000 0.97717678 628.84457 0.32414669 0.34016355 98000 0.97190208 634.37377 0.32366009 0.3398341 99000 0.98687379 640.66666 0.32356902 0.33950845 100000 0.97559757 646.96406 0.32348203 0.33919036 Loop time of 9.58779 on 8 procs for 100000 steps with 3200 atoms Performance: 4505729.040 tau/day, 10429.928 timesteps/s 99.4% CPU use with 8 MPI tasks x no OpenMP threads MPI task timing breakdown: Section | min time | avg time | max time |%varavg| %total --------------------------------------------------------------- Pair | 4.8572 | 4.9363 | 4.9822 | 1.7 | 51.49 Neigh | 1.3583 | 1.376 | 1.3991 | 1.2 | 14.35 Comm | 1.5192 | 1.7079 | 1.8264 | 7.2 | 17.81 Output | 0.0085125 | 0.0086059 | 0.0089455 | 0.1 | 0.09 Modify | 0.77663 | 0.7903 | 0.81378 | 1.3 | 8.24 Other | | 0.7686 | | | 8.02 Nlocal: 400 ave 413 max 391 min Histogram: 2 1 0 2 0 0 1 1 0 1 Nghost: 204.75 ave 213 max 197 min Histogram: 1 1 0 1 0 3 0 1 0 1 Neighs: 2800.62 ave 2959 max 2661 min Histogram: 1 1 1 2 0 0 0 1 1 1 Total # of neighbors = 22405 Ave neighs/atom = 7.00156 Neighbor list builds = 12728 Dangerous builds = 0 Total wall time: 0:00:10