Hello cp2k users,<br /><br />I have a question:<br />I did a Cell Optimization calculation wiht PBE where I got a lattice parameter of 12.04 Angstrom, very comparable to the experimental value of 12.00 Angstrom.<br />I did the same Cell Optimization calculation with the PBE0 functional and I reached a value of 12.66 Angstrom.<br />I would have expected a much more accurate value with the hybrid functional PBE0, because it is at a higher level of theory than PBE (GGA).<br />This is the input with PBE0:<br /> &GLOBAL<br /> PRINT_LEVEL MEDIUM<br /> PROJECT_NAME YAG_Cell_Opt_PBE0<br /> RUN_TYPE CELL_OPT<br /> &END GLOBAL<br /> &MOTION<br /> &GEO_OPT<br /> TYPE MINIMIZATION<br /> OPTIMIZER BFGS<br /> &END GEO_OPT<br /> &CELL_OPT<br /> OPTIMIZER BFGS<br /> STEP_START_VAL 0<br /> TYPE DIRECT_CELL_OPT<br /> EXTERNAL_PRESSURE 1.01325<br /> KEEP_ANGLES F<br /> CONSTRAINT NONE<br /> MAX_ITER 55<br /> &END CELL_OPT<br /> &END MOTION<br /> &FORCE_EVAL<br /> METHOD QS<br /> STRESS_TENSOR NUMERICAL<br /> &DFT<br /> BASIS_SET_FILE_NAME BASIS_MOLOPT<br /> POTENTIAL_FILE_NAME GTH_POTENTIALS<br /> UKS T<br /> &SCF <br /> EPS_SCF 1.0E-6 <br /> SCF_GUESS ATOMIC<br /> MAX_SCF 40<br /> &OUTER_SCF<br /> EPS_SCF 1.0E-6<br /> MAX_SCF 10<br /> &END<br /> &OT<br /> PRECONDITIONER FULL_ALL<br /> ENERGY_GAP 0.01<br /> MINIMIZER DIIS<br /> &END OT<br /> &END SCF<br /> &QS<br /> EPS_DEFAULT 1.0E-12<br /> EXTRAPOLATION PS<br /> EXTRAPOLATION_ORDER 3<br /> &END QS<br /> &MGRID<br /> NGRIDS 5<br /> CUTOFF 1.0E+03<br /> &END MGRID<br /> &XC<br /> &XC_FUNCTIONAL<br /> &HYB_GGA_XC_PBEH<br /> &END HYB_GGA_XC_PBEH<br /> &END XC_FUNCTIONAL<br /> &VDW_POTENTIAL<br /> POTENTIAL_TYPE PAIR_POTENTIAL<br /> &PAIR_POTENTIAL<br /> TYPE DFTD3<br /> PARAMETER_FILE_NAME dftd3.dat<br /> REFERENCE_FUNCTIONAL PBE0<br /> &END PAIR_POTENTIAL<br /> &END VDW_POTENTIAL<br /> &END XC<br /> &END DFT<br /> &SUBSYS<br /> &CELL<br /> ABC 10.428963 10.425980 10.422698<br /> ALPHA_BETA_GAMMA 109.488998 109.446965 109.467607<br /> MULTIPLE_UNIT_CELL 1 1 1<br /> PERIODIC XYZ<br /> &END CELL<br /> &COORD<br /> Y 4.3486154075 4.2950842437 5.3196321417<br /> Y 6.0853801970 4.9085728776 2.1264300032<br /> Y 0.8733519996 4.9086354625 6.3814665358<br /> Y -2.6039527163 5.5231448838 5.3183558093<br /> Y 2.6142292948 1.8376696577 7.4479257149<br /> Y 2.6104101807 -1.8494422097 7.4466343156<br /> Y -0.8679078589 0.6061511303 3.1848232795<br /> Y -2.6096620784 -0.0060013279 6.3852591732<br /> Y 2.6041558660 -0.0038382850 2.1250261938<br /> Y 6.0834319810 -0.6208194459 3.1903508061<br /> Y 0.8874597824 3.0724750414 1.0744993086<br /> Y 0.8678625775 6.7476472161 1.0619868504<br /> Al -4.3401797156 3.0666410058 7.4459145277<br /> Al 7.8239583099 1.8382466581 1.0609773693<br /> Al 4.3481852536 0.6074591571 5.3183312957<br /> Al -2.6058416050 7.3656069378 2.1275852154<br /> Al -0.8724634040 -3.0790149325 7.4541127408<br /> Al -0.8668340968 2.4508526313 6.3813575493<br /> Al 0.8697992788 -0.6212374139 5.3177074395<br /> Al 6.0867059132 -2.4641018496 6.3861781139<br /> Al 4.3476829482 2.4514793065 2.1270041167<br /> Al 4.3453596930 7.9813585672 1.0632856461<br /> Al -0.8641339919 4.2940160096 3.1806708091<br /> Al 2.6094075151 5.5237881248 3.1924879195<br /> Al 3.4780061828 -2.4645228071 4.2534793022<br /> Al -1.7345177407 4.9028549793 -0.0008404008<br /> Al 1.7442397885 2.4512376308 4.2507171849<br /> Al 5.2159918908 7.3667403364 4.2577468855<br /> Al -0.0028370613 0.0007453533 0.0014624368<br /> Al 6.9568761263 2.4513328230 4.2522104807<br /> Al 3.4733145743 4.9093119456 0.0046021722<br /> Al -1.7330852162 4.9094540457 8.5107603084<br /> O 7.5075288748 3.5448135803 0.6909828862<br /> O -3.6106794657 6.6794224052 3.4206823185<br /> O 3.3434293898 2.0700826218 5.2678623856<br /> O 3.3442936532 -3.8529544832 8.3338909406<br /> O 1.1766146360 -0.0943683626 6.9843208886<br /> O -1.2621218361 4.1288130379 6.8069741827<br /> O -3.9440500282 3.5381316372 5.7806631487<br /> O 0.8439983150 -3.5349206599 7.4996131276<br /> O 4.3758862880 3.5288586789 7.5003407681<br /> O 4.3726445326 -2.6498090728 5.9580202798<br /> O -0.4687473530 5.4962773570 4.4268562817<br /> O -2.5769210452 4.0188453295 3.5591255169<br /> O 4.6570298914 3.6278642230 0.8346522370<br /> O 4.6577057005 6.2739810367 0.6909168064<br /> O 3.0091558670 5.6878207415 6.8052442850<br /> O 1.8794467913 3.8418781493 8.3329005473<br /> O 5.3534857001 3.1379627645 3.4181995988<br /> O 2.2130493863 4.3166178058 4.4313348682<br /> O 4.3230131982 5.7989329898 3.5649817882<br /> O -0.8918134375 1.3817019783 1.0100428661<br /> O 7.5129238515 6.1888847103 0.8357805925<br /> O -4.7399695413 6.2823050798 5.7875223060<br /> O 4.0360795804 0.0759369721 6.9828458606<br /> O 1.8765596945 -2.0830820545 5.2654797961<br /> O -4.0289268457 1.3589527992 7.8150322246<br /> O 7.0885949913 -1.7767997945 5.0912209310<br /> O 0.1486988963 2.8326527826 3.2077847710<br /> O 0.1348731412 8.7566976189 0.1751906292<br /> O 2.2969254320 4.9887878171 1.5296449563<br /> O 4.7413334055 0.7740357399 1.7031908173<br /> O 7.4257555935 1.3648725048 2.7253363357<br /> O 2.6316767393 8.4396264484 1.0107170013<br /> O 1.6039732279 6.9850865553 3.2415661597<br /> O -0.5446734655 4.8207898308 1.5187893155<br /> O 8.2189340112 -1.3778170907 2.7274608059<br /> O 2.6338275702 2.2699327169 2.5503309564<br /> O -4.0268592569 -1.2909900428 7.6783113500<br /> O -0.8447499966 -0.8967438691 4.9518075545<br /> O 1.2652467388 0.5867172203 4.0782178985<br /> O -1.8684408437 1.7667358488 5.0862225871<br /> O 1.5961776646 1.0684387815 0.1880829885<br /> O 0.4693664543 -0.7878757737 1.7045268561<br /> O -1.2010653126 -1.3757187417 7.8452401269<br /> O -1.1769830276 1.2734933949 7.6736182844<br /> O 6.0618178007 0.8837624038 4.9462859223<br /> O 3.9492781834 -0.5972007421 4.0782685631<br /> O -0.8917912137 7.5502764746 2.5498560978<br /> O 0.8445124902 2.6368645034 5.9491672804<br /> &END COORD<br /> &KIND Al<br /> BASIS_SET DZVP-MOLOPT-SR-GTH<br /> POTENTIAL GTH-PBE0-q3<br /> &END KIND<br /> &KIND Y<br /> BASIS_SET DZVP-MOLOPT-SR-GTH<br /> POTENTIAL GTH-PBE0-q11<br /> &END KIND<br /> &KIND O<br /> BASIS_SET DZVP-MOLOPT-SR-GTH<br /> POTENTIAL GTH-PBE0-q6<br /> &END KIND<br /> &END SUBSYS<br /> &END FORCE_EVAL<br /><br /><br />Did I make some mistake?<br /><div><br /></div><div>(Obviously I reported the lattice distance of a cubic cell containing 160 atoms, while I used a primitive cell containing 80 atoms. The conversion was simple)</div><div><br /></div><div>Thanks a lot </div><div><br /></div><div>Alberto </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:cp2k+unsubscribe@googlegroups.com">cp2k+unsubscribe@googlegroups.com</a>.<br />
To view this discussion on the web visit <a href="https://groups.google.com/d/msgid/cp2k/2b3419f2-8d80-4fff-a0cb-edfde10e33b4n%40googlegroups.com?utm_medium=email&utm_source=footer">https://groups.google.com/d/msgid/cp2k/2b3419f2-8d80-4fff-a0cb-edfde10e33b4n%40googlegroups.com</a>.<br />