标题: CUTOFF收敛测试结果不稳定 [打印本页] 作者Author: aipacino 时间: 4 hour ago 标题: CUTOFF收敛测试结果不稳定 各位老师，我想考察磷酸水体系的质子状态，选好泛函和基组后测试CUTOFF，发现能量呈现阶梯式下降，这种情况应该如何确定CUTOFF的值？以下是我的输入文件
#Generated by Multiwfn (http://sobereva.com/multiwfn)
&GLOBAL
PROJECT guess
PRINT_LEVEL MEDIUM
RUN_TYPE ENERGY_FORCE
&END GLOBAL
&FORCE_EVAL
METHOD Quickstep
&SUBSYS
&CELL
A 13.51000000 0.00000000 0.00000000
B 0.00000000 13.51000000 0.00000000
C 0.00000000 0.00000000 13.51000000
PERIODIC XYZ #Direction(s) of applied PBC (geometry aspect)
&END CELL
&TOPOLOGY
COORD_FILE_NAME mix.xyz
COORD_FILE_FORMAT XYZ
&END TOPOLOGY
&KIND O
ELEMENT O
BASIS_SET TZV2P-MOLOPT-GTH-q6
BASIS_SET AUX_FIT admm-tzp-q6
POTENTIAL GTH-PBE0-q6
&END KIND
&KIND H
ELEMENT H
BASIS_SET TZV2P-MOLOPT-GTH-q1
BASIS_SET AUX_FIT admm-tzp-q1
POTENTIAL GTH-PBE0-q1
&END KIND
&KIND P
ELEMENT P
BASIS_SET TZV2P-MOLOPT-GTH-q5
BASIS_SET AUX_FIT admm-tzp-q5
POTENTIAL GTH-PBE0-q5
&END KIND
&END SUBSYS
&DFT
BASIS_SET_FILE_NAME BASIS_MOLOPT
BASIS_SET_FILE_NAME BASIS_MOLOPT_UCL
BASIS_SET_FILE_NAME BASIS_ADMM_UZH
POTENTIAL_FILE_NAME POTENTIAL_UZH
WFN_RESTART_FILE_NAME guess-RESTART.wfn
CHARGE 1 #Net charge
MULTIPLICITY 1 #Spin multiplicity
&QS
EPS_DEFAULT 1.0E-12 #Set all EPS_xxx to values such that the energy will be correct up to this value
EPS_PGF_ORB 1E-15 #If warning "Kohn Sham matrix not 100% occupied" occurs and meantime calculation is unstable, decrease it
&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
PARAMETRIZATION REVPBE
SCALE_X 0.75
SCALE_C 1.0
&END PBE
&END XC_FUNCTIONAL
&XC_GRID
XC_DERIV SPLINE2
&END XC_GRID
&HF
FRACTION 0.25
&SCREENING
EPS_SCHWARZ 1.0E-8
SCREEN_ON_INITIAL_P T
&END SCREENING
&MEMORY
MAX_MEMORY 4000
EPS_STORAGE_SCALING 0.1
&END MEMORY
&INTERACTION_POTENTIAL
POTENTIAL_TYPE TRUNCATED
CUTOFF_RADIUS 6
T_C_G_DATA ./t_c_g.dat
&END
&HF_INFO
&END HF_INFO
&END
&VDW_POTENTIAL
POTENTIAL_TYPE PAIR_POTENTIAL
&PAIR_POTENTIAL
PARAMETER_FILE_NAME dftd3.dat
TYPE DFTD3(BJ)
R_CUTOFF 15
LONG_RANGE_CORRECTION TRUE
REFERENCE_FUNCTIONAL revPBE0
#CALCULATE_C9_TERM T #Calculate C9-related three-body term, more accurate for large system
&END PAIR_POTENTIAL
&END VDW_POTENTIAL
&END XC
&AUXILIARY_DENSITY_MATRIX_METHOD
METHOD BASIS_PROJECTION
ADMM_PURIFICATION_METHOD MO_DIAG
&END AUXILIARY_DENSITY_MATRIX_METHOD
&MGRID
CUTOFF 1000
REL_CUTOFF 80
NGRIDS 5
&END MGRID
&SCF
MAX_SCF 128
EPS_SCF 3.0E-08 #Convergence threshold of density matrix of inner SCF
SCF_GUESS RESTART #Use wavefunction from WFN_RESTART_FILE_NAME file as initial guess
# IGNORE_CONVERGENCE_FAILURE #Continue calculation even if SCF not converged, works for version >= 2024.1
&OT
PRECONDITIONER FULL_ALL #Usually best but expensive for large system. Cheaper: FULL_SINGLE_INVERSE and FULL_KINETIC
MINIMIZER DIIS #CG is worth to consider in difficult cases
LINESEARCH 2PNT #1D line search algorithm for CG. 2PNT is default. 3PNT is more expensive but may be better. GOLD is best but very expensive
ALGORITHM STRICT #Algorithm of OT. Can be STRICT (default) or IRAC
&END OT
&PRINT
&RESTART #Note: Use "&RESTART OFF" can prevent generating .wfn file
BACKUP_COPIES 0 #Maximum number of backup copies of wfn file. 0 means never
&END RESTART
&END PRINT
&END SCF
&END DFT
&PRINT
&FORCES ON #Print atomic forces
&END FORCES
&END PRINT
&END FORCE_EVAL