<div dir="ltr">Dear CP2K users,<div> </div><div>Now I'm running the AIMD simulation for CO molecule at 300K under NVT ensemble to calculate the time averaged energy. But I found the temperature fluctuation is very large (even for 2ps), while the energy seems quite converged. I attached part of my CO.ener file here and the end is my input file. Is this case normal and can I use the averaged energy from the fifth column? Thanks a lot for your help in advance.</div><div> </div><div>Best regards,</div><div>Wanlu</div><div> </div><div>part of the CO.ener file:</div><div># Step Nr. Time[fs] Kin.[a.u.] Temp[K] Pot.[a.u.] Cons Qty[a.u.] UsedTime[s] 0 0.000000 0.001425067 300.000000000 -21.617781192 -21.616356125 0.000000000 1 1.000000 0.000692729 145.830941811 -21.617837920 -21.616358277 194.412350386 2 2.000000 0.000839725 176.775929504 -21.617886447 -21.616360106 46.210681908 3 3.000000 0.001256199 264.450456994 -21.617967921 -21.616363102 57.633208051 4 4.000000 0.000374173 78.769638799 -21.617973412 -21.616363182 46.150063051 5 5.000000 0.000559107 117.701236643 -21.617953442 -21.616361844 59.398619272 6 6.000000 0.002482481 522.602979873 -21.617783307 -21.616353176 106.069239420 7 7.000000 0.001196440 251.870238012 -21.617652842 -21.616346215 58.390943444 8 8.000000 0.001901098 400.212437908 -21.617651021 -21.616345218 58.502904797 9 9.000000 0.000855354 180.066031924 -21.617744300 -21.616349141 31.228304488 10 10.000000 0.001273480 268.088528685 -21.618056502 -21.616361811 66.249216199 11 11.000000 0.001148365 241.749723441 -21.618101233 -21.616363020 65.788505557 12 12.000000 0.001337372 281.538780360 -21.618040656 -21.616360497 50.228434081 13 13.000000 0.001088173 229.078325293 -21.617815635 -21.616351586 65.527550608 14 14.000000 0.000638396 134.392771993 -21.617717647 -21.616347841 30.803143926 15 15.000000 0.001131299 238.157024534 -21.617750654 -21.616349105 30.703742482 16 16.000000 0.000882749 185.833161270 -21.618016211 -21.616359839 58.420952012 17 17.000000 0.000704309 148.268604187 -21.618111383 -21.616364232 66.953019950 18 18.000000 0.000984427 207.238102770 -21.618056478 -21.616362640 65.433037204 19 19.000000 0.001300278 273.729917837 -21.617730686 -21.616349611 66.888907175 20 20.000000 0.001251339 263.427334256 -21.617350722 -21.616332279 57.671368687 21 21.000000 0.000071510 15.053991338 -21.617118557 -21.616320874 58.848506088 22 22.000000 0.000328659 69.188061889 -21.617273411 -21.616328474 50.358033484 23 23.000000 0.001961162 412.856931729 -21.617839418 -21.616354578 65.594630019 24 24.000000 0.003432034 722.499539826 -21.618087842 -21.616363528 65.576697189 25 25.000000 0.002137357 449.948804690 -21.617944687 -21.616356561 50.318810575 26 26.000000 0.000282373 59.444052481 -21.617674167 -21.616345681 50.183309429 27 27.000000 0.001428911 300.809318861 -21.617405859 -21.616335405 50.280129558 28 28.000000 0.001230288 258.995910868 -21.617190458 -21.616327303 60.631839060 29 29.000000 0.000778815 163.953411483 -21.617239252 -21.616329041 59.914822529 30 30.000000 0.001037451 218.400572007 -21.617555040 -21.616341263 58.026954871 31 31.000000 0.000257021 54.107232870 -21.617836485 -21.616352741 63.273706142 32 32.000000 0.000815204 171.613774933 -21.617983436 -21.616358974 51.766234757 33 33.000000 0.002147387 452.060254251 -21.618044023 -21.616365491 65.707532154 34 34.000000 0.001059117 222.961601928 -21.617875727 -21.616358444 42.327060248 35 35.000000 0.000556875 117.231265217 -21.617833972 -21.616356575 38.473901298 36 36.000000 0.002660563 560.092203650 -21.617900280 -21.616359371 38.686128197 37 37.000000 0.000306512 64.525842654 -21.618022387 -21.616364623 58.028456304 38 38.000000 0.001094222 230.351784002 -21.618059911 -21.616366229 30.907870563 39 39.000000 0.002375479 500.077458607 -21.618094890 -21.616365658 65.868519638 40 40.000000 0.001059975 223.142157446 -21.617922951 -21.616358024 66.814346387 41 41.000000 0.002150347 452.683436556 -21.617727451 -21.616350173 58.576830784 42 42.000000 0.000955871 201.226516876 -21.617573183 -21.616344211 58.266955604 43 43.000000 0.003461060 728.609943461 -21.617553106 -21.616343260 81.233679124 44 44.000000 0.003689339 776.666432065 -21.617708084 -21.616348597 59.117384726 45 45.000000 0.002945410 620.057281651 -21.617936220 -21.616357146 60.046403246 46 46.000000 0.004584184 965.046120081 -21.618135902 -21.616363905 119.776386127 47 47.000000 0.001211722 255.087403714 -21.618101005 -21.616362177 80.983581299 48 48.000000 0.003172557 667.875357276 -21.618027232 -21.616358757 57.963843688 49 49.000000 0.002787604 586.836497994 -21.617921379 -21.616353596 58.793182783 50 50.000000 0.001320236 277.931380619 -21.617895704 -21.616352103 58.655742473 51 51.000000 0.001349890 284.173930376 -21.617975899 -21.616356500 81.564031711 52 52.000000 0.004197290 883.598537868 -21.618093592 -21.616362967 93.771222658 53 53.000000 0.000804420 169.343569457 -21.618143900 -21.616365817 84.571369800 54 54.000000 0.001340079 282.108729947 -21.618089714 -21.616364198 86.971021005 55 55.000000 0.001111101 233.904941648 -21.618038691 -21.616362607 65.827716856 56 56.000000 0.001635646 344.330302044 -21.618001500 -21.616361434 38.540800519 57 57.000000 0.000383350 80.701385444 -21.617996052 -21.616361311 65.489763892 58 58.000000 0.000581642 122.445243901 -21.618027478 -21.616362320 57.710738976 59 59.000000 0.000637017 134.102594542 -21.618072549 -21.616363699 57.981170168 60 60.000000 0.000256226 53.939856452 -21.618106586 -21.616364617 58.548539240 61 61.000000 0.000276851 58.281711503 -21.618134608 -21.616365048 58.458087666 62 62.000000 0.001327029 279.361436939 -21.618142721 -21.616364759 58.208439551 63 63.000000 0.000305662 64.346965320 -21.618138401 -21.616363258 57.932972059 64 64.000000 0.000792654 166.866636174 -21.618141563 -21.616362838 46.120169683 65 65.000000 0.000968894 203.968166349 -21.618163658 -21.616363286 30.770339062 66 66.000000 0.001585392 333.751027453 -21.618228272 -21.616365914 81.433016635 67 67.000000 0.003230830 680.142887167 -21.618248138 -21.616366576 57.805929371 68 68.000000 0.004550695 957.996018285 -21.618173297 -21.616364727 85.084943491 69 69.000000 0.001315308 276.894023628 -21.618119388 -21.616363118 38.600684694 70 70.000000 0.002560177 538.959267435 -21.618098609 -21.616362903 40.223963304 71 71.000000 0.001819033 382.936419195 -21.618079845 -21.616362398 90.782305011 72 72.000000 0.000517145 108.867468032 -21.618072415 -21.616363269 59.907460252 73 73.000000 0.000564062 118.744295312 -21.618059739 -21.616363893 59.481724930 74 74.000000 0.000521309 109.744026596 -21.618038633 -21.616363840 59.628348131 75 75.000000 0.002132719 448.972441454 -21.618004901 -21.616363063 61.541181826 76 76.000000 0.000535457 112.722531882 -21.617998466 -21.616362945 25.172890818 77 77.000000 0.000791883 166.704365624 -21.617996265 -21.616363155 40.223652923 78 78.000000 0.001431101 301.270260395 -21.618006814 -21.616363694 40.042347613 79 79.000000 0.001260725 265.403370341 -21.618019664 -21.616364007 39.697757854 80 80.000000 0.000110691 23.302251401 -21.618026769 -21.616364035 41.031351849 81 81.000000 0.001271648 267.702757536 -21.618039910 -21.616364022 40.622016474 82 82.000000 0.001943523 409.143432763 -21.618051808 -21.616363856 40.130044182 83 83.000000 0.002089133 439.796797555 -21.618072968 -21.616363811 59.343040636 84 84.000000 0.002634760 554.660284803 -21.618104400 -21.616364023 60.067878875 85 85.000000 0.002369065 498.727210926 -21.618147035 -21.616364725 85.188466185 86 86.000000 0.000799557 168.319960767 -21.618169688 -21.616364951 60.087728120 87 87.000000 0.001556181 327.601699012 -21.618191051 -21.616365285 59.620458533 88 88.000000 0.001500868 315.957459040 -21.618206771 -21.616365513 59.495860192 89 89.000000 0.000521386 109.760310787 -21.618210141 -21.616365465 60.615616803 90 90.000000 0.000642020 135.155667286 -21.618194752 -21.616364400 60.373461886 91 91.000000 0.000287061 60.431151866 -21.618191018 -21.616364295 24.119875298 92 92.000000 0.000548709 115.512238254 -21.618190786 -21.616364325 23.668599707 93 93.000000 0.001219521 256.729274925 -21.618195472 -21.616364513 40.134158431 94 94.000000 0.002274151 478.746167486 -21.618202538 -21.616364616 41.108107413 95 95.000000 0.002352777 495.298222687 -21.618207847 -21.616364591 40.475635013 96 96.000000 0.000042770 9.003762756 -21.618210327 -21.616364411 40.231778402 97 97.000000 0.000644745 135.729403123 -21.618213635 -21.616364382 23.213505859 98 98.000000 0.000375875 79.127780711 -21.618227316 -21.616364562 58.810299742 99 99.000000 0.002188839 460.786546096 -21.618248055 -21.616364869 60.821353728 100 100.000000 0.000810643 170.653709364 -21.618263919 -21.616365060 59.688553417 </div><div>... ... (the phenomenon looks unchanged even upon 2ps)</div><div> </div><div>Here is the input:</div><div> </div><div>&FORCE_EVAL METHOD QS &PRINT &FORCES ON &END &END &DFT BASIS_SET_FILE_NAME BASIS_MOLOPT_UCL POTENTIAL_FILE_NAME GTH_POTENTIALS &MGRID CUTOFF 400 REL_CUTOFF 60 &END MGRID &QS EPS_DEFAULT 1.0E-12 WF_INTERPOLATION ASPC &END QS &SCF SCF_GUESS RESTART MAX_SCF 500 ADDED_MOS 500 CHOLESKY INVERSE &SMEAR ON METHOD FERMI_DIRAC ELECTRONIC_TEMPERATURE [K] 300 &END SMEAR &DIAGONALIZATION ALGORITHM STANDARD &END DIAGONALIZATION &MIXING METHOD BROYDEN_MIXING ALPHA 0.1 BETA 1.5 NBROYDEN 8 &END MIXING &PRINT &RESTART ADD_LAST NUMERIC &EACH QS_SCF 0 &END EACH &END RESTART &END PRINT &END SCF &XC &XC_FUNCTIONAL &LIBXC FUNCTIONAL XC_MGGA_XC_B97M_V &END LIBXC &END XC_FUNCTIONAL &vdW_POTENTIAL DISPERSION_FUNCTIONAL NON_LOCAL &NON_LOCAL TYPE RVV10 PARAMETERS 6.0 0.01 KERNEL_FILE_NAME /usr/common/usg/cp2k/6.1/data/rVV10_kernel_table.dat &END NON_LOCAL &END vdW_POTENTIAL &XC_GRID XC_DERIV NN50_SMOOTH &END XC_GRID &END XC &END DFT &SUBSYS &CELL ABC 15.363 15.363 43.902 ALPHA_BETA_GAMMA 90.0 90.0 120. &END CELL &COORD @INCLUDE 'CO.xyz' &END COORD &KIND C BASIS_SET TZVP-MOLOPT-GTH POTENTIAL GTH-PBE-q4 &END KIND &KIND O BASIS_SET TZVP-MOLOPT-GTH POTENTIAL GTH-PBE-q6 &END KIND &END SUBSYS &END FORCE_EVAL &GLOBAL PROJECT MD_CO RUN_TYPE MD PRINT_LEVEL LOW &END GLOBAL </div><div>&MD ENSEMBLE NVT STEPS 100000 TIMESTEP 1.0 TEMPERATURE 300.0 &THERMOSTAT REGION GLOBAL TYPE CSVR &CSVR TIMECON [fs] 1. &END CSVR &END THERMOSTAT &END MD &PRINT &TRAJECTORY &EACH MD 10 &END EACH &END TRAJECTORY &RESTART &EACH MD 1 &END EACH &END RESTART &END PRINT &END MOTION </div></div>