You can find some good quality basis sets in in BASIS_MOLOPT_UCL:<div><br></div><div>https://github.com/cp2k/cp2k/blob/master/data/BASIS_MOLOPT_UCL</div><div><br></div><div>there are also some alternative Lanthanide basis sets available in other files.</div><div><br></div><div>Matt<br><br></div><div class="gmail_quote"><div dir="auto" class="gmail_attr">On Wednesday, November 25, 2020 at 2:44:47 PM UTC sh...@gmail.com wrote:<br/></div><blockquote class="gmail_quote" style="margin: 0 0 0 0.8ex; border-left: 1px solid rgb(204, 204, 204); padding-left: 1ex;"><div>Dear Fabian,</div><div>Thanks for the explanation! I've noticed the CELL_REF and OT issues of the input file. The CP2K output file also hints about the OT algorithm. <br></div><div>The reason I use DZV-GTH-PADE basis for Y is that I cannot find GTH-PBE basis set for it in the cp2k/data directory. Maybe I should find the corresponding basis set in somewhere else.</div><div>Anyway, thanks for your help and suggestions!</div><div><br></div><div>Best regards.</div><div>Huaiyang Sun<br></div><br><div class="gmail_quote"><div dir="auto" class="gmail_attr">On Wednesday, November 25, 2020 at 3:26:58 PM UTC+8 <a href data-email-masked rel="nofollow">fa...@gmail.com</a> wrote:<br></div><blockquote class="gmail_quote" style="margin:0 0 0 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><div>Dear Huaiyang Sun,</div><div><br></div><div>Many solids have a bulk modulus in the range of 1 to 100 GPa. A material with a bulk modulus of 10 GPa changes its volume by 1% when subjected to a pressure of 1000 bar. In this case a PRESSURE_TOLERANCE of 100 bar is already accurate to within 0.1% of the volume.<br></div><div><br></div><div></div><div>The input file has some issues:</div><div>use CELL_REF for a cell optimization</div><div>you cannot use OT together with k-points, use DIAGONALIZATION instead</div><div>I would recomment to not mix different basis sets, especially not using PADE ones for PBE calculations</div><div><br></div><div>Cheers,</div><div>Fabian<br></div><div class="gmail_quote"><div dir="auto" class="gmail_attr">On Wednesday, 25 November 2020 at 04:09:02 UTC+1 <a rel="nofollow">sh...@gmail.com</a> wrote:<br></div><blockquote class="gmail_quote" style="margin:0 0 0 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><br><div>Deal all,</div><div><br></div><div>I'm doing a cell optimisation run of a YAG (Y3Al5O12) crystal. I wonder about the meaning of the tags EXTERNAL_PRESSURE and PRESSURE_TOLERANCE in the CELL_OPT section of the input. The default values are both 100 bar. Here are the few points I don't understand,</div><div><br></div><div>1. If the cell optimisation run is targeted at the input EXTERNAL_PRESSURE, shouldn't the default PRESSURE_TOLERANCE be given a much smaller value, like 5.0 or 1.0 bar?</div><div><br></div><div>2. Why 100 bar? 1 atm = 1.013 bar sounds more reasonable.</div><div><br></div><div>3. My simple understanding of cell optimisation is to find the minimum point of the energy-volume (E-V) curve. Then what's the role of external pressure?</div><div><br></div><div>Here is my input file.</div><div><br></div><div>&GLOBAL<br> project pristine-opt<br> run_type CELL_OPT<br> print_level MEDIUM<br>&END GLOBAL<br><br>&FORCE_EVAL<br> METHOD QS<br><br> &SUBSYS<br> &CELL <br> ABC 12.0003 12.0003 12.0003 <br> PERIODIC XYZ <br> MULTIPLE_UNIT_CELL 1 1 1<br> SYMMETRY CUBIC <br> &END CELL<br><br> &TOPOLOGY<br> MULTIPLE_UNIT_CELL 1 1 1<br> COORD_FILE_FORMAT XYZ<br> COORD_FILE_NAME <a href="http://yag_from_cif_conven_unit.xyz" rel="nofollow" target="_blank" data-saferedirecturl="https://www.google.com/url?hl=en&q=http://yag_from_cif_conven_unit.xyz&source=gmail&ust=1606401991244000&usg=AFQjCNGzTnWA23XNglxVkpWq6guULPgTQg">yag_from_cif_conven_unit.xyz</a> <br> &END TOPOLOGY<br><br> &KIND Y<br> ELEMENT Y<br> BASIS_SET DZV-GTH-PADE<br> POTENTIAL GTH-PBE-q11<br> &END KIND <br><br><br> &KIND Al<br> ELEMENT Al<br> BASIS_SET DZVP-MOLOPT-SR-GTH <br> POTENTIAL GTH-PBE-q3<br> &END KIND <br><br> &KIND O<br> ELEMENT O<br> BASIS_SET DZVP-GTH-PBE<br> POTENTIAL GTH-PBE-q6<br> &END KIND<br><br> &KIND Ce<br> ELEMENT Ce<br> BASIS_SET DZVP-MOLOPT-SR-GTH-q12<br> POTENTIAL GTH-PBE-q12<br> &END KIND<br><br> &KIND Yb<br> ELEMENT Yb<br> BASIS_SET DZVP-MOLOPT-SR-GTH-q24<br> POTENTIAL GTH-PBE-q24<br> &END KIND<br><br> &END SUBSYS<br><br> &DFT<br> BASIS_SET_FILE_NAME BASIS_SET_YAG<br> POTENTIAL_FILE_NAME POTENTIAL_YAG<br><br> &MGRID<br> NGRIDS 4<br> CUTOFF 600<br> REL_CUTOFF 60<br> &END MGRID<br><br> &QS<br> EPS_DEFAULT 1.0E-12<br> &END QS<br><br> &POISSON<br> PERIODIC XYZ<br> &END POISSON<br><br> &SCF<br> SCF_GUESS ATOMIC<br> EPS_SCF 5.0E-7<br> MAX_SCF 200 <br><br> CHOLESKY INVERSE <br><br> &OT ON<br> MINIMIZER DIIS<br> &END OT<br> #&DIAGONALIZATION <br> # ALGORITHM STANDARD<br> #&END DIAGONALIZATION <br><br> # ADDED_MOS 30<br> #<br> # &SMEAR ON<br> # METHOD FERMI_DIRAC<br> # ELECTRONIC_TEMPERATURE [K] 300<br> #&END SMEAR <br><br> # &MIXING<br> # METHOD BROYDEN_MIXING<br> # ALPHA 0.4<br> # BETA 0.5<br> # NBROYDEN 8<br> # &END MIXING <br> &END SCF<br><br> &XC<br> &XC_FUNCTIONAL PBE<br> &END XC_FUNCTIONAL <br> &END XC<br><br> &KPOINTS<br> EPS_GEO 1.0E-5<br> SCHEME MONKHORST 3 3 3<br> &END KPOINTS<br> &END DFT<br><br> &PRINT<br> &TOTAL_NUMBERS ON<br> &END TOTAL_NUMBERS<br> &END PRINT<br> <br> STRESS_TENSOR ANALYTICAL <br>&END FORCE_EVAL<br><br>&MOTION<br> &GEO_OPT<br> OPTIMIZER LBFGS<br> TYPE MINIMIZATION<br> MAX_DR 5.0E-4<br> MAX_FORCE 5.0E-4<br> RMS_DR 5.0E-4<br> RMS_FORCE 5.0E-4<br> MAX_ITER 500<br> &END GEO_OPT<br><br> &CELL_OPT<br> TYPE DIRECT_CELL_OPT<br> OPTIMIZER LBFGS<br> KEEP_SYMMETRY<br> MAX_DR 5.0E-4<br> MAX_FORCE 1.0E-4<br> RMS_DR 5.0E-4<br> RMS_FORCE 5.0E-4<br> # defaults for p and delta p [bar]<br> EXTERNAL_PRESSURE 100.0 0.0 0.0 0.0 100.0 0.0 0.0 0.0 100.0<br> PRESSURE_TOLERANCE 100.0<br> &END CELL_OPT<br>&END MOTION <br></div><div><br></div><div><br></div><div><br></div><div><br></div><div>Thank you,</div><div>Huaiyang Sun<br></div><div><br></div></blockquote></div></blockquote></div></blockquote></div>