Hi everybody,
I have a simple question. When I use MP scheme(from 25 meV to 1000 meV every
25 meV incensement) with 9*9*9 (I made a test with 18*18*18 K while nothing
changed) Kpoints, I can't obtain convergence in SCF steps (mixing value
0.04, 0.06 or 0.1). It is not the question of the amount of SCF steps (I use
about 100 steps), since at some point the dDmax and E_tot stop changing with
dDmax values 0.0005-0.0010
However, when I turned to Fermi-Dirac smearing and it works quite
predictably.
I just want to understand why MP smearing doesn't work well in my case?
Has anybody actually used MP smearing in SIESTA?
I found that Oleksandr Voznyy used to ask the same question, but I didn't
find the reply.
I will really appreciate if anyone can help!
My convergence is like this:
..
siesta: iscf Eharris(eV) E_KS(eV) FreeEng(eV) dDmax Ef(eV)
siesta: 1 -1541.1055 -1540.8935 -1540.8909 0.0114 -7.5336
siesta: 2 -1541.1168 -1541.0468 -1541.0434 0.0124 -7.7179
siesta: 3 -1541.1177 -1540.9686 -1540.9661 0.0073 -7.6176
siesta: 4 -1541.1186 -1541.0182 -1541.0151 0.0029 -7.6203
siesta: 5 -1541.1187 -1541.0512 -1541.0481 0.0009 -7.6121
siesta: 6 -1541.1188 -1541.0475 -1541.0443 0.0005 -7.6135
siesta: 7 -1541.1188 -1541.0443 -1541.0412 0.0004 -7.6148
siesta: 8 -1541.1188 -1541.0443 -1541.0412 0.0004 -7.6148
siesta: 9 -1541.1188 -1541.0448 -1541.0417 0.0004 -7.6149
siesta: 10 -1541.1188 -1541.0448 -1541.0417 0.0004 -7.6149
siesta: 11 -1541.1188 -1541.0449 -1541.0417 0.0004 -7.6150
siesta: 12 -1541.1188 -1541.0449 -1541.0418 0.0004 -7.6151
siesta: 13 -1541.1188 -1541.0449 -1541.0418 0.0004 -7.6151
siesta: 14 -1541.1188 -1541.0450 -1541.0418 0.0004 -7.6152
siesta: 15 -1541.1188 -1541.0450 -1541.0419 0.0004 -7.6153
siesta: 16 -1541.1188 -1541.0450 -1541.0419 0.0004 -7.6153
siesta: 17 -1541.1188 -1541.0450 -1541.0419 0.0004 -7.6154
siesta: 18 -1541.1188 -1541.0451 -1541.0419 0.0004 -7.6154
siesta: 19 -1541.1188 -1541.0451 -1541.0420 0.0004 -7.6155
siesta: 20 -1541.1188 -1541.0451 -1541.0420 0.0004 -7.6155
siesta: 21 -1541.1188 -1541.0451 -1541.0420 0.0004 -7.6155
siesta: 22 -1541.1188 -1541.0452 -1541.0420 0.0004 -7.6156
siesta: 23 -1541.1188 -1541.0452 -1541.0421 0.0004 -7.6156
siesta: 24 -1541.1188 -1541.0452 -1541.0421 0.0004 -7.6156
siesta: 25 -1541.1188 -1541.0452 -1541.0421 0.0004 -7.6156
siesta: 26 -1541.1188 -1541.0452 -1541.0421 0.0004 -7.6157
siesta: 27 -1541.1188 -1541.0453 -1541.0421 0.0004 -7.6157
siesta: 28 -1541.1188 -1541.0453 -1541.0422 0.0004 -7.6157
siesta: 29 -1541.1188 -1541.0453 -1541.0422 0.0004 -7.6157
siesta: 30 -1541.1188 -1541.0453 -1541.0422 0.0004 -7.6157
siesta: 31 -1541.1188 -1541.0453 -1541.0422 0.0004 -7.6157
siesta: 32 -1541.1188 -1541.0454 -1541.0422 0.0004 -7.6157
siesta: 33 -1541.1188 -1541.0454 -1541.0422 0.0004 -7.6158
siesta: 34 -1541.1188 -1541.0454 -1541.0423 0.0004 -7.6158
siesta: 35 -1541.1188 -1541.0454 -1541.0423 0.0004 -7.6158
siesta: 36 -1541.1188 -1541.0454 -1541.0423 0.0004 -7.6158
siesta: 37 -1541.1188 -1541.0454 -1541.0423 0.0004 -7.6158
siesta: 38 -1541.1188 -1541.0454 -1541.0423 0.0004 -7.6158
siesta: 39 -1541.1188 -1541.0454 -1541.0423 0.0004 -7.6158
siesta: 40 -1541.1188 -1541.0454 -1541.0423 0.0004 -7.6158
siesta: 41 -1541.1188 -1541.0455 -1541.0423 0.0004 -7.6158
siesta: 42 -1541.1188 -1541.0455 -1541.0424 0.0004 -7.6158
siesta: 43 -1541.1188 -1541.0455 -1541.0424 0.0004 -7.6158
siesta: 44 -1541.1188 -1541.0455 -1541.0424 0.0004 -7.6158
siesta: 45 -1541.1188 -1541.0455 -1541.0424 0.0004 -7.6158
siesta: 46 -1541.1188 -1541.0455 -1541.0424 0.0004 -7.6158
siesta: 47 -1541.1188 -1541.0455 -1541.0424 0.0005 -7.6158
siesta: 48 -1541.1188 -1541.0455 -1541.0424 0.0005 -7.6158
siesta: 49 -1541.1188 -1541.0456 -1541.0424 0.0005 -7.6158
siesta: 50 -1541.1188 -1541.0456 -1541.0424 0.0005 -7.6158
siesta: 51 -1541.1188 -1541.0456 -1541.0424 0.0005 -7.6158
siesta: 52 -1541.1188 -1541.0456 -1541.0425 0.0005 -7.6158
siesta: 53 -1541.1188 -1541.0456 -1541.0425 0.0005 -7.6158
siesta: 54 -1541.1188 -1541.0456 -1541.0425 0.0005 -7.6158
siesta: 55 -1541.1188 -1541.0456 -1541.0425 0.0005 -7.6158
siesta: 56 -1541.1188 -1541.0456 -1541.0425 0.0005 -7.6158
siesta: 57 -1541.1188 -1541.0456 -1541.0425 0.0005 -7.6158
siesta: 58 -1541.1188 -1541.0456 -1541.0425 0.0005 -7.6158
siesta: 59 -1541.1188 -1541.0456 -1541.0425 0.0005 -7.6159
siesta: 60 -1541.1188 -1541.0456 -1541.0425 0.0005 -7.6159
siesta: 61 -1541.1188 -1541.0456 -1541.0425 0.0005 -7.6159
siesta: 62 -1541.1188 -1541.0456 -1541.0425 0.0005 -7.6159
siesta: 63 -1541.1188 -1541.0456 -1541.0425 0.0005 -7.6159
siesta: 64 -1541.1188 -1541.0456 -1541.0425 0.0005 -7.6159
siesta: 65 -1541.1188 -1541.0456 -1541.0425 0.0005 -7.6159
siesta: 66 -1541.1188 -1541.0456 -1541.0425 0.0005 -7.6159
siesta: 67 -1541.1188 -1541.0456 -1541.0425 0.0005 -7.6159
siesta: 68 -1541.1188 -1541.0457 -1541.0425 0.0005 -7.6159
siesta: 69 -1541.1188 -1541.0457 -1541.0425 0.0005 -7.6159
siesta: 70 -1541.1188 -1541.0457 -1541.0425 0.0005 -7.6159
siesta: 71 -1541.1188 -1541.0457 -1541.0425 0.0005 -7.6159
siesta: 72 -1541.1188 -1541.0457 -1541.0425 0.0005 -7.6159
siesta: 73 -1541.1188 -1541.0457 -1541.0425 0.0005 -7.6159
siesta: 74 -1541.1188 -1541.0457 -1541.0426 0.0005 -7.6159
siesta: 75 -1541.1188 -1541.0457 -1541.0426 0.0005 -7.6159
siesta: 76 -1541.1188 -1541.0457 -1541.0426 0.0005 -7.6159
siesta: 77 -1541.1188 -1541.0457 -1541.0426 0.0005 -7.6159
siesta: 78 -1541.1188 -1541.0457 -1541.0426 0.0005 -7.6159
siesta: 79 -1541.1188 -1541.0457 -1541.0426 0.0005 -7.6159
siesta: 80 -1541.1188 -1541.0457 -1541.0426 0.0005 -7.6159
siesta: 81 -1541.1188 -1541.0457 -1541.0426 0.0005 -7.6159
siesta: 82 -1541.1188 -1541.0457 -1541.0426 0.0005 -7.6159
siesta: 83 -1541.1188 -1541.0457 -1541.0426 0.0005 -7.6159
siesta: 84 -1541.1188 -1541.0457 -1541.0426 0.0005 -7.6159
siesta: 85 -1541.1188 -1541.0457 -1541.0426 0.0005 -7.6159
siesta: 86 -1541.1188 -1541.0457 -1541.0426 0.0005 -7.6159
siesta: 87 -1541.1188 -1541.0457 -1541.0426 0.0005 -7.6159
siesta: 88 -1541.1188 -1541.0457 -1541.0426 0.0005 -7.6159
siesta: 89 -1541.1188 -1541.0457 -1541.0426 0.0005 -7.6159
siesta: 90 -1541.1188 -1541.0457 -1541.0426 0.0005 -7.6159
siesta: 91 -1541.1188 -1541.0457 -1541.0426 0.0005 -7.6159
siesta: 92 -1541.1188 -1541.0457 -1541.0426 0.0005 -7.6159
siesta: 93 -1541.1188 -1541.0457 -1541.0426 0.0005 -7.6159
siesta: 94 -1541.1188 -1541.0457 -1541.0426 0.0005 -7.6159
siesta: 95 -1541.1188 -1541.0457 -1541.0426 0.0005 -7.6159
siesta: 96 -1541.1188 -1541.0457 -1541.0426 0.0005 -7.6159
siesta: 97 -1541.1188 -1541.0457 -1541.0426 0.0005 -7.6159
siesta: 98 -1541.1188 -1541.0457 -1541.0426 0.0005 -7.6159
siesta: 99 -1541.1188 -1541.0457 -1541.0426 0.0005 -7.6159
.
This is my input file:
SystemName bcc Fe ferro GGA # Descriptive name of the system
SystemLabel Fe # Short name for naming files
# Output options
WriteCoorXmol .true.
WriteForces .true.
WriteCoorStep
WriteMullikenPop 1
# Species and atoms
NumberOfSpecies 1
NumberOfAtoms 2
%block ChemicalSpeciesLabel
1 26 Fe
%endblock ChemicalSpeciesLabel
# Basis
PAO.EnergyShift 50 meV
#PAO.BasisSize DZP
%block PAO.Basis
Fe 2 split
n=4 0 2 P
5.58 0.
n=3 2 1
5.58
%endblock PAO.Basis
LatticeConstant 2.8887 Ang
%block LatticeVectors
1.00000 0.000000 0.000000
0.00000 1.000000 0.000000
0.00000 0.000000 1.000000
%endblock LatticeVectors
#KgridCutoff 15. Ang
%block kgrid_Monkhorst_Pack
9 0 0 0.5
0 9 0 0.5
0 0 9 0.5
%endblock kgrid_Monkhorst_Pack
%block BandLines
1 0.00000 0.000000 0.000000 \Gamma
40 2.00000 0.000000 0.000000 H
28 1.00000 1.000000 0.000000 N
28 0.00000 0.000000 0.000000 \Gamma
34 1.00000 1.000000 1.000000 P
%endblock BandLines
xc.functional GGA # Exchange-correlation functional
xc.authors PBE # Exchange-correlation version
SpinPolarized true # Logical parameters are: yes or no
MeshCutoff 450. Ry # Mesh cutoff. real space mesh
# SCF options
MaxSCFIterations 100 # Maximum number of SCF iter
DM.MixingWeight 0.04 # New DM amount for next SCF cycle
DM.Tolerance 1.d-4 # Tolerance in maximum difference
# between input and output DM
DM.UseSaveDM F # to use continuation files
DM.NumberPulay 8
Diag.DivideAndConquer .false.
SolutionMethod diagon # OrderN or Diagon
ElectronicTemperature 175 meV # Temp. for Fermi smearing
OccupationFunction MP
# MD options
MD.VariableCell T
MD.TypeOfRun cg # Type of dynamics:
MD.NumCGsteps 100 # Number of CG steps for
# coordinate optimization
MD.MaxCGDispl 0.1 Ang # Maximum atomic displacement
# in one CG step (Bohr)
MD.MaxForceTol 0.04 eV/Ang # Tolerance in the maximum
# atomic force (Ry/Bohr)
MD.MaxStressTol 1 GPa
# Atomic coordinates
AtomicCoordinatesFormat Fractional
%block AtomicCoordinatesAndAtomicSpecies
0.000000000000 0.000000000000 0.000000000000 1
0.500000000000 0.500000000000 0.500000000000 1
%endblock AtomicCoordinatesAndAtomicSpecies
Best
Lela
