Hi,<div> </div><div>for the restart I used the last restart file of the previous run, modifying the parameters in $QS or $SCF to test the new ones.</div><div>I observed a drift also for NVE even if most of the tests have been done for NVT.</div><div>I will carry out more tests for NVE to reduce the number of variables and avoid also the problem of thermostat setting.</div><div> </div><div>About the drift, after few ps it is about 10^-3 au, depending on the simulations. </div><div>Changing the parameters to increase the accuracy, in some cases I observed no drift but sudden jumps in the total energy.</div><div> </div><div>I will keep you updated about further NVE tests.</div><div>Thanks</div><div> </div><div>alberto</div><div> Il giorno martedì 11 settembre 2012 11:04:00 UTC+2, jgh ha scritto:<blockquote class="gmail_quote" style="margin: 0;margin-left: 0.8ex;border-left: 1px #ccc solid;padding-left: 1ex;">Hi it is difficult to give good advice without more information. Possible problems might be: - Restarts: do you correctly restart all variables - Thermostat: I don't know if the setting you have is reasonable and adequate for this timestep. Do you see a drift also for NVE? - How big is the drift and how long is your trajectory? regards Juerg -------------------------------------------------------------- Juerg Hutter Phone : ++41 44 635 4491 Physical Chemistry Institute FAX : ++41 44 635 6838 University of Zurich E-mail: <a href="javascript:" target="_blank" gdf-obfuscated-mailto="thmt2iRsq5wJ">hut...@pci.uzh.ch</a> Winterthurerstrasse 190 CH-8057 Zurich, Switzerland --------------------------------------------------------------- -----<a href="javascript:" target="_blank" gdf-obfuscated-mailto="thmt2iRsq5wJ">cp...@googlegroups.com</a> wrote: ----- To: <a href="javascript:" target="_blank" gdf-obfuscated-mailto="thmt2iRsq5wJ">cp...@googlegroups.com</a> From: "<a href="javascript:" target="_blank" gdf-obfuscated-mailto="thmt2iRsq5wJ">albe...@virgilio.it</a>" Sent by: <a href="javascript:" target="_blank" gdf-obfuscated-mailto="thmt2iRsq5wJ">cp...@googlegroups.com</a> Date: 09/11/2012 10:06AM Subject: Re: [CP2K:4024] Energy conservation NVT/NVE simulation Dear Juerg, thank you very much. I changed the functional to BLYP and I used ASPC interpolator. I carried out different tests where I tried different values of the EXTRAPOLATION_ORDER (up to 6), I increased the EPS_SCF and used defaults for most of the other parameters. Unfortunately, I still observe either drifts or jumps in the total energy. I think that there is still a problem in the input, reported below. Many thanks for your help. Alberto ************ &FORCE_EVAL METHOD QS &DFT BASIS_SET_FILE_NAME GTH_BASIS_SETS POTENTIAL_FILE_NAME GTH_POTENTIALS &MGRID CUTOFF 300 REL_CUTOFF 40 &END MGRID &QS EPS_DEFAULT 1.0E-12 WF_INTERPOLATION ASPC EXTRAPOLATION_ORDER 3 &END QS &SCF SCF_GUESS ATOMIC EPS_SCF 1.0E-6 &OT T &END OT &PRINT &RESTART OFF &END &END &END SCF &XC &XC_FUNCTIONAL BLYP &END XC_FUNCTIONAL &END XC &PRINT &MOMENTS MEDIUM &END &END PRINT &END DFT &SUBSYS &CELL ABC 9.8528 9.8528 9.8528 &END CELL # 32 H2O (TIP5P,1bar,300K) a = 9.8528 &COORD O 2.280398 9.146539 5.088696 O 1.251703 2.406261 7.769908 O 1.596302 6.920128 0.656695 O 2.957518 3.771868 1.877387 O 0.228972 5.884026 6.532308 O 9.023431 6.119654 0.092451 O 7.256289 8.493641 5.772041 O 5.090422 9.467016 0.743177 O 6.330888 7.363471 3.747750 O 7.763819 8.349367 9.279457 O 8.280798 3.837153 5.799282 O 8.878250 2.025797 1.664102 O 9.160372 0.285100 6.871004 O 4.962043 4.134437 0.173376 O 2.802896 8.690383 2.435952 O 9.123223 3.549232 8.876721 O 1.453702 1.402538 2.358278 O 6.536550 1.146790 7.609732 O 2.766709 0.881503 9.544263 O 0.856426 2.075964 5.010625 O 6.386036 1.918950 0.242690 O 2.733023 4.452756 5.850203 O 4.600039 9.254314 6.575944 O 3.665373 6.210561 3.158420 O 3.371648 6.925594 7.476036 O 5.287920 3.270653 6.155080 O 5.225237 6.959594 9.582991 O 0.846293 5.595877 3.820630 O 9.785620 8.164617 3.657879 O 8.509982 4.430362 2.679946 O 1.337625 8.580920 8.272484 O 8.054437 9.221335 1.991376 H 1.762019 9.820429 5.528454 H 3.095987 9.107088 5.588186 H 0.554129 2.982634 8.082024 H 1.771257 2.954779 7.182181 H 2.112148 6.126321 0.798136 H 1.776389 7.463264 1.424030 H 3.754249 3.824017 1.349436 H 3.010580 4.524142 2.466878 H 0.939475 5.243834 6.571945 H 0.515723 6.520548 5.877445 H 9.852960 6.490366 0.393593 H 8.556008 6.860063 -0.294256 H 7.886607 7.941321 6.234506 H 7.793855 9.141028 5.315813 H 4.467366 9.971162 0.219851 H 5.758685 10.102795 0.998994 H 6.652693 7.917443 3.036562 H 6.711966 7.743594 4.539279 H 7.751955 8.745180 10.150905 H 7.829208 9.092212 8.679343 H 8.312540 3.218330 6.528858 H 8.508855 4.680699 6.189990 H 9.742249 1.704975 1.922581 H 8.799060 2.876412 2.095861 H 9.505360 1.161677 6.701213 H 9.920117 -0.219794 7.161006 H 4.749903 4.186003 -0.758595 H 5.248010 5.018415 0.403676 H 3.576065 9.078451 2.026264 H 2.720238 9.146974 3.273164 H 9.085561 4.493058 9.031660 H 9.215391 3.166305 9.749133 H 1.999705 2.060411 1.927796 H 1.824184 0.564565 2.081195 H 7.430334 0.849764 7.438978 H 6.576029 1.537017 8.482885 H 2.415851 1.576460 8.987338 H 2.276957 0.099537 9.289499 H 1.160987 1.818023 4.140602 H 0.350256 2.874437 4.860741 H 5.768804 2.638450 0.375264 H 7.221823 2.257514 0.563730 H 3.260797 5.243390 5.962382 H 3.347848 3.732214 5.988196 H 5.328688 9.073059 5.982269 H 5.007063 9.672150 7.334875 H 4.566850 6.413356 3.408312 H 3.273115 7.061666 2.963521 H 3.878372 7.435003 6.843607 H 3.884673 6.966316 8.283117 H 5.918240 3.116802 5.451335 H 5.355924 2.495093 6.711958 H 5.071858 7.687254 10.185667 H 6.106394 7.112302 9.241707 H 1.637363 5.184910 4.169264 H 0.427645 4.908936 3.301903 H 9.971698 7.227076 3.709104 H 10.647901 8.579244 3.629806 H 8.046808 5.126383 2.213838 H 7.995317 4.290074 3.474723 H 1.872601 7.864672 7.930401 H 0.837635 8.186808 8.987268 H 8.314696 10.115534 2.212519 H 8.687134 8.667252 2.448452 &END COORD &KIND H BASIS_SET TZV2P-GTH POTENTIAL GTH-BLYP-q1 &END KIND &KIND O BASIS_SET TZV2P-GTH POTENTIAL GTH-BLYP-q6 &END KIND &END SUBSYS &END FORCE_EVAL &GLOBAL PROJECT H2O-32 RUN_TYPE MD PRINT_LEVEL MEDIUM &TIMINGS THRESHOLD 0.000001 &END &END GLOBAL &MOTION &MD ENSEMBLE NVT STEPS 30000 TIMESTEP 0.5 TEMPERATURE 300.0 &THERMOSTAT TYPE CSVR &CSVR TIMECON 100.0 &END CSVR &END THERMOSTAT &END MD &PRINT &VELOCITIES LOW &END &END PRINT &END MOTION ************** Il giorno mercoledì 5 settembre 2012 09:56:16 UTC+2, jgh ha scritto:Hi the main problem is &QS EPS_DEFAULT 1.0E-12 WF_INTERPOLATION PS EXTRAPOLATION_ORDER 3 &END QS change to WF_INTERPOLATION ASPC (the default) and maybe increase the EXTRAPOLATION_ORDER slightly. See J. Hutter, Car-Parrinello molecular dynamics Wiley Interdisciplinary Reviews: Computational Molecular Science 2 (4) , pp. 604-612 for an explanation. You should also change to a more reasonable DFT functional. LDA (PADE) will lead to an extremly overstructured system. See J. Schmidt et al., Isobaric-isothermal molecular dynamics simulations utilizing density functional theory: An assessment of the structure and density of water at near-ambient conditions Journal of Physical Chemistry B Volume 113, Issue 35, 3 September 2009, Pages 11959-11964 regards Juerg -------------------------------------------------------------- Juerg Hutter Phone : ++41 44 635 4491 Physical Chemistry Institute FAX : ++41 44 635 6838 University of Zurich E-mail: <a>hut...@pci.uzh.ch</a> Winterthurerstrasse 190 CH-8057 Zurich, Switzerland --------------------------------------------------------------- -----<a>cp...@googlegroups.com</a> wrote: ----- To: <a>cp...@googlegroups.com</a> From: "<a>albe...@virgilio.it</a>" Sent by: <a>cp...@googlegroups.com</a> Date: 09/05/2012 09:44AM Subject: [CP2K:4010] Energy conservation NVT/NVE simulation Dear all, I'm carrying out some tests to reproduce the VDOS of water and I used as starting points the input files 'H2O-32.inp' and 'H2O-64.inp' in tests/QS/benchmark directory. In both cases I ran a NVT simulation at 300K for 15 ps followed by an NVE simulation on the equilibrated system. I'm puzzled about the results in the energies: in both NVT and NVE the plot of "Cons Qty" show a constant and linear drift while temperature, kinetic and potential energy are equilibrated and stable. Since "Cons Qty" should be conserved and this is not the case I think that there are some problems in the setup of the simulation. I did not modify the parameters of the benchmark inputs but I just added the thermostat section in NVT and I modified only the printing option. Thank you very much for your help and suggestions, Alberto -- You received this message because you are subscribed to the Google Groups "cp2k" group. To view this discussion on the web visit <a href="https://groups.google.com/d/msg/cp2k/-/LgSDjVEpz0YJ" target="_blank">https://groups.google.com/d/msg/cp2k/-/LgSDjVEpz0YJ</a>. To post to this group, send email to <a>cp...@googlegroups.com</a>. To unsubscribe from this group, send email to <a>cp2k+...@googlegroups.com</a>. For more options, visit this group at <a href="http://groups.google.com/group/cp2k?hl=en" target="_blank">http://groups.google.com/group/cp2k?hl=en</a>. -- You received this message because you are subscribed to the Google Groups "cp2k" group. To view this discussion on the web visit <a href="https://groups.google.com/d/msg/cp2k/-/yrA7tbiv8B4J" target="_blank">https://groups.google.com/d/msg/cp2k/-/yrA7tbiv8B4J</a>. To post to this group, send email to <a href="javascript:" target="_blank" gdf-obfuscated-mailto="thmt2iRsq5wJ">cp...@googlegroups.com</a>. To unsubscribe from this group, send email to <a href="javascript:" target="_blank" gdf-obfuscated-mailto="thmt2iRsq5wJ">cp2k+uns...@googlegroups.com</a>. For more options, visit this group at <a href="http://groups.google.com/group/cp2k?hl=en" target="_blank">http://groups.google.com/group/cp2k?hl=en</a>. </blockquote></div>