The usual suspects apply: decrease the mixing weight to 0.05 or even 0.01, if necessary.
Happy New Year, Marcos 2010/12/31 guohuaihong <[email protected]> > Dear siesta community: > > > I am having trouble to get a SCF calculation converged for a layered composite > system. Can somebody give me a hand? > > > Our system is "graphene n layers on top of Ni(111) surface". I am using GGA > > pseudopotentials for Ni and C elements. When a simplest SZ basis set is used, > > SCF calculation can converge. However, as it comes to the standard DZP basis > > set, SCF convergence becomes difficult. I don't know what to do to improve it. > > Here is my input file: > ===========start of input.fdf==== ============ > SystemName 2Ni-2gra > SystemLabel 2Ni-2gra > NumberOfAtoms 6 > Diag.ParallelOverK T > > PAO.BasisSize DZ > > NumberOfSpecies 2 > %block ChemicalSpeciesLabel > 1 28 Ni > 2 6 C > %endblock ChemicalSpeciesLabel > > LatticeConstant 2.48901587 Ang > > %block LatticeVectors > 0.866025404 -0.500000 0.00000000 > 0.866025404 0.500000 0.00000000 > 0.000000000 0.000000 12.05295650 > %endblock LatticeVectors > > %block kgrid_Monkhorst_Pack > 6 0 0 0.0 > 0 6 0 0.0 > 0 0 1 0.0 > %endblock kgrid_Monkhorst_Pack > > SpinPolarized .false. > XC_functional GGA > XC_authors PBE > > %block PS.lmax > C 2 > %endblock PS.lmax > > PAO.EnergyShift 50. meV > > MeshCutoff 200. Ry > DM.UseSaveDM F > MaxSCFiterations 200 > DM.MixingWeight 0.10 > DM.NumberPulay 3 > DM.Tolerance 0.0001 > > MD.NumCGsteps 100 > MD.TypeOfRun CG > MD.UseSaveXV T > MD.UseSaveCG   ; F > WriteMDXmol F > WriteForces T > > SaveDeltaRho F > SaveRho F > > %block GeometryConstraints > position from 1 to 1 > %endblock GeometryConstraints > > AtomicCoordinatesFormat Ang > %block AtomicCoordinatesAndAtomicSpecies > 1.15470054 0.000 1.6256505400 1 #Ni > 1.73205081 0.000 2.4336003900 1 #Ni > 1.73205081 0.000 3.2861461800 2 #C > 2.30940108 0.000 3.2861461800 2 #C > 2.30940108&n bsp; 0.000 4.6320596600 2 #C > 2.88675135 0.000 4.6320596600 2 #C > %endblock AtomicCoordinatesAndAtomicSpecies > ===========end of input.fdf================ > > > Here is part of my output file: > ===========start of output.fdf================ > ..... > siesta: iscf Eharris(eV) E_KS(eV) FreeEng(eV) dDmax Ef(eV) > siesta: 1 -2512.1635 -2522.5031 -2522.5031 5.9203 -7.3552 > timer: Routine,Calls,Time,% = IterSCF 1 133.954 & nbsp;82.97 > elaps: Routine,Calls,Wall,% = IterSCF 1 11.239 82.68 > siesta: 2 -2798.2370 -2503.2791 -2503.2853 15.2607 0.1093 > siesta: 3 -2514.2022 -2519.9057 -2519.9121 6.0595 -7.7756 > siesta: 4 -2513.5115 -2516.6410 -2516.6423 7.7241 -3.7334 > siesta: 5 -2598.9529 -2517.6669 -2517.6798 5.9405 -1.3577 > siesta: 6 -2541.5296 -2518.7682 -2518.7715& > nbsp; 8.9084 -1.1456 > siesta: 7 -2604.5084 -2510.6025 -2510.6047150.0320 -0.4481 > siesta: 8 -3121.8587 -2483.1835 -2483.1859598.3458 1.7518 > siesta: 9 -2977.9663 -2491.9150 -2491.9182596.9323 4.0476 > siesta: 10 -3078.4553 -2498.1912 -2498.1984 62.3984 0.6857 > siesta: 11 -4356.4281 -2361.6155 -2361.6199609.8885-39.3225 > siesta: 12 -4489.7671 -2325.6771 -2325.6775599.9060-47.2102 > siesta : 13 -4360.2034 -2338.9801 -2338.9801600.4145-43.2638 > siesta: 14 -3448.0593 -2205.6430 -2205.6430 71.0008-56.8998 > siesta: 15 -2579.5160 -2300.5191 -2300.5276 65.1504-24.0299 > siesta: 16 -2525.8003 -2327.3343 -2327.3529 82.7621-16.0542 > siesta: 17 -2555.9318 -2346.6249 -2346.6364 48.8877-15.5471 > siesta: 18 -3513.9083 -2395.8520 -2395.8576 54.9869-12.0970 > ...... > ===========end of output.fdf================ > > Any& nbsp;suggestion is appreciated. Thanks alot! > > Best wishes! > > HHG > > > > > > > -- > Magnetism and Magnetic Materials Division > Shenyang Materials Science National Laboratory > Institute of Metal Research > Chinese Academy of Sciences > 72 Wenhua Road,Shenyang 110016, China > > > +86-15140243901 (mobile) > work: [email protected] > > >
