问题现象描述: 各位好,我最近自己分别用cp2k和VASP跑了一个H在SiC四面体间隙中的间隙形成能的例子,想要测试一下cp2k对比VASP的计算速度,两个计算都考虑了自旋,且K点为4*4*4,晶胞加上H一共有65个原子,cp2k采用的是DZVP-MOLOPT-SR-GTH基组以及GTH-PBE赝势,cp2k输入文件通过Multwfn直接产生,几乎没怎么修改(初步结构优化,后续还用TZVP-MOLOPT-GTH和TZV2P-MOLOPT-GTH基组做了能量计算,能量和VASP对得上),然而目前这一步cp2k耗时1069秒,VASP只用了377秒,cp2k采用cp2k.popt提交,两个计算都采用了36核提交 下面是结构以及cp2k和VASP的主要的输入文件内容 问题: 1.现在cp2k用时比VASP用时高,是由于cp2k对k点的支持问题吗,还是cp2k的in文件有需要改进的地方 2.我现在采取的用DZVP-MOLOPT-SR-GTH结构优化之后,再用TZVP-MOLOPT-GTH进行能量计算的流程是否是合理的 输入文件(cp2k和VASP) cp2k:(结构部分省略) &KIND Si ELEMENT Si BASIS_SET DZVP-MOLOPT-SR-GTH-q4 POTENTIAL GTH-PBE &END KIND &KIND C ELEMENT C BASIS_SET DZVP-MOLOPT-SR-GTH-q4 POTENTIAL GTH-PBE &END KIND &KIND H ELEMENT H BASIS_SET DZVP-MOLOPT-SR-GTH-q1 POTENTIAL GTH-PBE &END KIND &END SUBSYS &DFT BASIS_SET_FILE_NAME BASIS_MOLOPT POTENTIAL_FILE_NAME POTENTIAL # WFN_RESTART_FILE_NAME SiC_222_HTsi-RESTART.wfn CHARGE 0 #Net charge MULTIPLICITY 2 #Spinmultiplicity UKS &KPOINTS SCHEME MONKHORST-PACK 4 4 4 &END KPOINTS &QS EPS_DEFAULT 1.0E-12 #Set all EPS_xxx to values such that the energy willbe correct up to this value #EXTRAPOLATION USE_PREV_P #Use converged density matrix of last geometryas initial guess &END QS &POISSON PERIODIC XYZ #Direction(s) of PBC for calculating electrostatics PSOLVER PERIODIC #The way to solve Poisson equation &END POISSON &XC &XC_FUNCTIONAL PBE &END XC_FUNCTIONAL &END XC &MGRID CUTOFF 400 REL_CUTOFF 55 &END MGRID &SCF MAX_SCF 128 EPS_SCF 1.0E-06 #Convergence threshold of density matrix of inner SCF # SCF_GUESS RESTART #Use wavefunction from WFN_RESTART_FILE_NAME file asinitial guess &DIAGONALIZATION ALGORITHM STANDARD #Algorithm for diagonalization. DAVIDSON is fasterfor large systems &END DIAGONALIZATION &MIXING #How to mix old and new density matrices METHOD BROYDEN_MIXING #PULAY_MIXING is also a good alternative ALPHA 0.4 #Default. Mixing 40% of new density matrix with the old one NBROYDEN 8 #Default is 4. Number of previous steps stored for the actualmixing scheme &END MIXING &PRINT &RESTART #Note: Use "&RESTART OFF" can preventgenerating .wfn file BACKUP_COPIES 0 #Maximum number of backup copies of wfn file. 0 meansnever &END RESTART &END PRINT &END SCF &END DFT &END FORCE_EVAL &MOTION &GEO_OPT TYPE MINIMIZATION #Search for minimum KEEP_SPACE_GROUP F #If T, then space group will be detected andpreserved OPTIMIZER BFGS #Can also be CG (more robust for difficult cases) orLBFGS &BFGS TRUST_RADIUS 0.2 #Trust radius (maximum stepsize) in Angstrom # RESTART_HESSIAN T #If read initial Hessian, uncomment this line andspecify the file in the next line # RESTART_FILE_NAME to_be_specified &END BFGS MAX_ITER 500 #Maximum number of geometry optimization MAX_DR 3E-3 #Maximum geometry change RMS_DR 1.5E-3 #RMS geometry change MAX_FORCE 4.5E-4 #Maximum force RMS_FORCE 3E-4 #RMS force &END GEO_OPT &PRINT &TRAJECTORY FORMAT xyz &END TRAJECTORY &RESTART BACKUP_COPIES 0 #Maximum number of backing up restart file, 0 means never &END RESTART &END PRINT &END MOTION
VASP: INCAR: SYSTEM = graphite cell ISTART = 0 ICHARG = 2 IBRION = 2 ISIF = 2 ENCUT = 450 NELMIN = 2 NELM = 100 EDIFF = 1e-5 EDIFFG = -0.02 NSW = 100 ISMEAR = 0 SIGMA = 0.05 ISPIN = 2 #MAGMOM = 92*2.5 #IVDW = 11 LCHARG = .F. LWAVE = .F. NPAR = 4 #KPAR = 4 KPOINTS: auto mesh 0 G 4 4 4 0 0 0
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