<div dir="ltr">I forgot to mention, when all commented things work well, if you want to thermalize the system after running a production dynamics, it is advisable to run the thermalization in two steps instead of just one run. I use a two step procedure, running first a thermalization with a short TIMECON (50 or 100 fs) and REGION MASSIVE, to have a strong coupling and fast temperature stabilization, then restart using a higher TIMECON (200 fs or what you want for production) and REGION GLOBAL, restarting the thermostat between step 1 and 2. With this procedure usually you obtain a better thermalization in a short number of steps.<div><br></div><div>Regards</div></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">El vie, 23 jul 2021 a las 14:12, Lucas Lodeiro (<<a href="mailto:eluni...@gmail.com">eluni...@gmail.com</a>>) escribió:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><div dir="ltr">Hello Tingting Zhu,<br><div><br></div><div>As far as I know, to correct your errors in EOM, you have to reduce the time step to 0.5 fs when hydrogen atoms are present and high temperature (fast dynamics) is applied. Also you have a poor performance in the SCF cycle. The most important is your convergence criterion, defined by EPS_SCF. with your current value 1.0E-5 you are having error on the energy in the order of E-3 E-4, which is very high. REDUCING EPS_SCF and EPS_DEFAULT probably solve in part these problem. I usually use a relation (EPS_SCF)^2=EPS_DEFAULT.</div><div>Also, your CUTOFF is so low. You have to compute a convergence study first, to have good SCF results first, and then run the MD. At the forum, some people says a good guess for cutoff is REL_CUTOFF * HIGHER_GAUSSIAN_COEFFICIENT, in your case Mg has a hard PP, where the tighter gaussian has a coefficient of 30.65, then with a REL_CUTOFF=40 you need a CUTOFF=1200 or higher.</div><div><br></div><div>Regards - Lucas Lodeiro</div></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">El vie, 23 jul 2021 a las 8:01, 'Tingting Zhu' via cp2k (<<a href="mailto:cp...@googlegroups.com" target="_blank">cp...@googlegroups.com</a>>) escribió:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><div><br></div>Dear Marcella Iannuzzi<div><br><div><div>Ok, thank you! I will learn CP2K as your suggestion.</div><div><br></div><div>However, for the problem you pointed "the integral error of the equation of motion is large", I still don't know how to solve it? According to my current understanding, may I increase the value of EPS_SCF, CUTOFF, REL_CUTOFF, and decrease the value of TIMESTEP. Do you think it is appropriate?</div><div>For example, ( EPS_DEFAULT 1E-12, EPS_SCF=1.0E*10^6, CUTOFF=350, REL_CUTOFF=60, TIMESTEP=0.5) </div></div><div><br></div><div><div>Sincerely</div><div>Tingting Zhu</div></div><div><br></div><div><br></div><div><br></div><div><br></div><div><br></div><div><br></div><div><br><br></div></div><div class="gmail_quote"><div dir="auto" class="gmail_attr">在2021年7月23日星期五 UTC+8 下午4:18:42<Marcella Iannuzzi> 写道：<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">Dear Tingting Zhu<div><br></div><div>I quickly checked your energy file and indeed you have a serious drift in the total energy,</div><div>which indicates that the integration of the equations of motion has a large error. </div><div>If you do not have experience with ab initio MD, I suggest that you learn that first from reference literature. </div><div>The parameters are adjusted until converged results are obtained and known properties are reproduced. </div><div><br></div><div>Regards</div><div>Marcella</div><div><br><br></div><div class="gmail_quote"><div dir="auto" class="gmail_attr">On Friday, July 23, 2021 at 9:30:06 AM UTC+2 <a rel="nofollow">fe...@qq.com</a> wrote:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><div>Dear Marcella Iannuzzi</div><div>Since I am a beginner, although I have read a lot of documents about CP2K, I still lack experience in setting some parameters. In the input file, could you give me some suggestions about the settings of CUTOFF, SCF, EPS_SCF? There are 366 atoms in my system, containing Mg, Al, O, and H.</div><div>In addition, the input file, out file and corresponding trajectory file that I calculated before are put in the compressed package below.</div><div><br></div><div>The CP2K version I use is 7.1</div><div><br></div><div>Thank you very much!</div><div><br></div><div><br></div><div><br></div><br><div class="gmail_quote"><div dir="auto" class="gmail_attr">在2021年7月23日星期五 UTC+8 下午2:49:54<Marcella Iannuzzi> 写道：<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">Dear Tingting Zhu<div><br></div><div>One possible explanation is that the error in the forces and in the integration of the equations of motion is too big.</div><div>Some parameters in the input would indicate that, as too large TIMESTEP and EPS_SCF and too low CUTOFF. </div><div>This could be verified from the conservation of the total energy.</div><div>Without more information it is difficult to guess.</div><div><br></div><div>Regards</div><div>Marcella<br><br></div><div class="gmail_quote"><div dir="auto" class="gmail_attr">On Friday, July 23, 2021 at 8:34:17 AM UTC+2 <a rel="nofollow">fe...@qq.com</a> wrote:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><div>Dear all,</div><div><br></div><div>I am new to cp2k, I want to use CP2K's kinetics module to simulate the adsorption of water on the surface of MgAl2O4 (111) at 973K. However, with the increase of simulation time, the temperature keeps increasing, and there is no trend to stablize at the target temperature. My input file is as follows:</div><div><br></div><div>I also tried to modify the TIMECON parameter to 200fs or 400fs, but this problem always exists. Any idea whats going wrong here? </div><div><br></div><div>I need your help, Please do correct me if any information provided seems wrong</div><div><br></div><div><br></div><div><img alt="200-400 fs.png" width="378px" height="534px" src="https://groups.google.com/group/cp2k/attach/199de61a7b5ab/200-400%20fs.png?part=0.2&view=1"><br></div><div><img alt="200 fs.png" width="369px" height="534px" src="https://groups.google.com/group/cp2k/attach/199de61a7b5ab/200%20fs.png?part=0.1&view=1"><br></div><div><br></div><div><br></div><div><div>&GLOBAL</div><div> PROJECT MgAl2O4-14W-MD</div><div> PRINT_LEVEL LOW</div><div> RUN_TYPE MD</div><div>&END GLOBAL</div><div><br></div><div>&FORCE_EVAL</div><div> METHOD Quickstep</div><div> &SUBSYS</div><div> &CELL</div><div> A 17.33280000 0.00000000 0.00000000</div><div> B 0.00000000 20.01420000 0.00000000</div><div> C 0.00000000 0.00000000 28.56250000</div><div> PERIODIC XYZ #Direction of applied PBC (geometry aspect)</div><div> &END CELL</div><div> &COORD</div><div> Al 0.0000000000 3.3357667100 <a href="tel:(630)%20918-7500" value="+16309187500" rel="nofollow" target="_blank">1.6309187500</a></div><div> Al 2.<a href="tel:(888)%20857-7800" value="+18888577800" rel="nofollow" target="_blank">8888577800</a> 8.<a href="tel:(339)%20316-7100" value="+13393167100" rel="nofollow" target="_blank">3393167100</a> <a href="tel:(630)%20918-7500" value="+16309187500" rel="nofollow" target="_blank">1.6309187500</a></div><div> Al 5.7775422200 3.3357667100 <a href="tel:(630)%20918-7500" value="+16309187500" rel="nofollow" target="_blank">1.6309187500</a></div><div> Al 8.6664000000 8.<a href="tel:(339)%20316-7100" value="+13393167100" rel="nofollow" target="_blank">3393167100</a> <a href="tel:(630)%20918-7500" value="+16309187500" rel="nofollow" target="_blank">1.6309187500</a></div><div> Al 11.5552577800 3.3357667100 <a href="tel:(630)%20918-7500" value="+16309187500" rel="nofollow" target="_blank">1.6309187500</a></div><div>............</div><div> &END COORD</div><div># &VELOCITY #You can set initial atomic velocities in this section</div><div># &END VELOCITY</div><div> &KIND Al </div><div> ELEMENT Al</div><div> BASIS_SET DZVP-MOLOPT-SR-GTH</div><div> POTENTIAL GTH-PBE</div><div> &END KIND</div><div> &KIND Mg </div><div> ELEMENT Mg</div><div> BASIS_SET DZVP-MOLOPT-SR-GTH</div><div> POTENTIAL GTH-PBE</div><div> &END KIND</div><div> &KIND O </div><div> ELEMENT O </div><div> BASIS_SET DZVP-MOLOPT-SR-GTH</div><div> POTENTIAL GTH-PBE</div><div> &END KIND</div><div> &KIND H </div><div> ELEMENT H </div><div> BASIS_SET DZVP-MOLOPT-SR-GTH</div><div> POTENTIAL GTH-PBE</div><div> &END KIND</div><div> &END SUBSYS</div><div><br></div><div> &DFT</div><div> BASIS_SET_FILE_NAME /home/room/data/cp2k-7.1.0/data/BASIS_MOLOPT</div><div> POTENTIAL_FILE_NAME /home/room/data/cp2k-7.1.0/data/POTENTIAL</div><div># WFN_RESTART_FILE_NAME MgAl2O4-14W-MD-RESTART.wfn</div><div> CHARGE 0 #Net charge</div><div> MULTIPLICITY 1 #Spin multiplicity</div><div> &QS</div><div> EPS_DEFAULT 1E-10 #This is default. Set all EPS_xxx to values such that the energy will be correct up to this value</div><div> EXTRAPOLATION ASPC #Extrapolation for wavefunction during e.g. MD. ASPC is default, PS also be used</div><div> EXTRAPOLATION_ORDER 3 #Order for PS or ASPC extrapolation. 3 is default</div><div> &END QS</div><div> &POISSON</div><div> PERIODIC XYZ #Direction(s) of PBC for calculating electrostatics</div><div> PSOLVER PERIODIC #The way to solve Poisson equation</div><div> &END POISSON</div><div> &XC</div><div> &XC_FUNCTIONAL PBE</div><div> &END XC_FUNCTIONAL</div><div> &VDW_POTENTIAL</div><div> POTENTIAL_TYPE PAIR_POTENTIAL</div><div> &PAIR_POTENTIAL</div><div> PARAMETER_FILE_NAME dftd3.dat</div><div> TYPE DFTD3</div><div> REFERENCE_FUNCTIONAL PBE</div><div> &END PAIR_POTENTIAL</div><div> &END VDW_POTENTIAL</div><div> &END XC</div><div> &MGRID</div><div> CUTOFF 300</div><div> REL_CUTOFF 40</div><div> &END MGRID</div><div> &SCF</div><div> MAX_SCF 500 #Maximum number of steps of inner SCF</div><div> EPS_SCF 1.0E-05 #Convergence threshold of density matrix of inner SCF</div><div># SCF_GUESS RESTART #Use wavefunction from WFN_RESTART_FILE_NAME file as initial guess</div><div> &OT</div><div> PRECONDITIONER FULL_KINETIC #FULL_SINGLE_INVERSE is also worth to try. FULL_ALL is better but quite expensive for large system</div><div> MINIMIZER DIIS #CG is worth to consider in difficult cases</div><div> LINESEARCH 2PNT #1D line search algorithm for CG. 2PNT is default, 3PNT is better but more costly. GOLD is best but very expensive</div><div> &END OT</div><div> &OUTER_SCF</div><div> MAX_SCF 500 #Maximum number of steps of outer SCF</div><div> EPS_SCF 1.0E-05 #Convergence threshold of outer SCF</div><div> &END OUTER_SCF</div><div> &PRINT</div><div> &RESTART #Use "&RESTART OFF" can prevent generating wfn file</div><div> BACKUP_COPIES 0 #Maximum number of backup copies of wfn file</div><div> &END RESTART</div><div> &END PRINT</div><div> &END SCF</div><div> &END DFT</div><div>&END FORCE_EVAL</div><div><br></div><div>&MOTION</div><div> &MD</div><div> ENSEMBLE NVT</div><div> STEPS 5000</div><div> TIMESTEP 1.0 #fs. Decrease it properly for high temperature simulation</div><div> TEMPERATURE 973 #Initial and maintained temperature (K)</div><div> &THERMOSTAT</div><div> TYPE CSVR</div><div> &CSVR</div><div> TIMECON 200 #Time constant in fs. Smaller/larger results in stronger/weaker temperature coupling</div><div> &END CSVR </div><div> &DEFINE_REGION </div><div> LIST 193..366 </div><div> &END DEFINE_REGION </div><div> &END THERMOSTAT </div><div> &END MD </div><div> &CONSTRAINT</div><div> &FIXED_ATOMS #Set atoms to be fixed</div><div> COMPONENTS_TO_FIX XYZ #May also be e.g. Z, XY ...</div><div> LIST 1..192 </div><div> &END FIXED_ATOMS</div><div> &END CONSTRAINT</div><div> &PRINT</div><div> &TRAJECTORY</div><div> &EACH</div><div> MD 1 #Output frequency of geometry</div><div> &END EACH</div><div> FORMAT xyz</div><div> &END TRAJECTORY</div><div> &VELOCITIES</div><div> &EACH</div><div> MD 1 #Output frequency of velocity</div><div> &END EACH</div><div> &END VELOCITIES</div><div> &RESTART</div><div> BACKUP_COPIES 0 #Maximum number of backing up restart file</div><div> &EACH</div><div> MD 10 #Frequency of updating last restart file</div><div> &END EACH</div><div> &END RESTART</div><div> &END PRINT</div><div>&END MOTION </div></div><div><br></div><div><div>Thanks in advance!</div><div><br></div><div>Sincerely</div><div>Tingting Zhu</div></div><div><br></div><div><br></div></blockquote></div></blockquote></div></blockquote></div></blockquote></div> <p></p> -- <br> You received this message because you are subscribed to the Google Groups "cp2k" group.<br> To unsubscribe from this group and stop receiving emails from it, send an email to <a href="mailto:cp...@googlegroups.com" target="_blank">cp...@googlegroups.com</a>.<br> To view this discussion on the web visit <a href="https://groups.google.com/d/msgid/cp2k/42b20601-fd02-42d7-a588-3207082cf697n%40googlegroups.com?utm_medium=email&utm_source=footer" target="_blank">https://groups.google.com/d/msgid/cp2k/42b20601-fd02-42d7-a588-3207082cf697n%40googlegroups.com</a>.<br> </blockquote></div> </blockquote></div>