Try the setting as followed DM.MixingWeight 0.05 DM.NumberPulay 10 and increase the k_grid sampling, 6*6*1 is too small.
2011/1/1 Marcos Veríssimo Alves <[email protected]> > 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] >> >> >> >
