hybrid DFT for bulk

molecule san... at gmail.com
Fri Jul 18 23:09:42 CEST 2008


Hi Juerg,

Ok, I will do more tests for larger systems.
However, the behavior looks more like a bug rather than the
numerical errors caused by \Gamma-only sampling and the
minimum images.

-molecule


On Jul 18, 3:19 am, Juerg Hutter <hut... at pci.uzh.ch> wrote:
> Hi
>
> the exact exchange code in CP2K is still under development.
> Especially for periodic systems and non-short range 1/r.
> Currently the code is not stable for small unit cells.
> The size where it becomes stable depends on the system.
> These problems are related to the gamma point approximation
> and the minimum image convention, see the literature.
> That your system is a metal is a bonus problem.
>
> regards
>
> Juerg
>
> ----------------------------------------------------------
> Juerg Hutter                   Phone : ++41 44 635 4491
> Physical Chemistry Institute   FAX   : ++41 44 635 6838
> University of Zurich           E-mail: hut... at pci.uzh.ch
> Winterthurerstrasse 190
> CH-8057 Zurich, Switzerland
> ----------------------------------------------------------
>
>
>
> On Thu, 17 Jul 2008, sh ke wrote:
>
> > Hello, Dear All,
>
> > Has anyone done a hybrid DFT, like pbe0, calculation for bulks, like Au?
> > I did pbe0 and b3lyp calculations for bulk Au with a 4-atom unit cell
> > but the result
> > is a mess. Can anyone help?
>
> > .inp file:
>
> >  METHOD Quickstep
> >  &DFT
> > #
> > #   LSD
> > #   UKS F
> > #   ROKS F
> > #   MULTIPLICITY 0
> > #   PLUS_U_METHOD
> > #   CHARGE 0
> > #
> >    BASIS_SET_FILE_NAME ../BASIS_SET
> >    POTENTIAL_FILE_NAME ../POTENTIAL
> >    &MGRID
> >      CUTOFF 200
> >      REL_CUTOFF 50
> >    &END MGRID
> >    &QS
> >      METHOD GPW
> >    &END QS
> >    &POISSON
> >      PERIODIC XYZ
> >      PSOLVER PERIODIC
> >    &END POISSON
> >    &SCF
> > #     &OT on
> > #      PRECONDITIONER FULL_ALL
> > #      MINIMIZER DIIS
> > #     &END OT
> >      ADDED_MOS 21
> >      MIXING 0.1
> >      SMEAR 0.1
> >      MAX_DIIS 5
> >      EPS_SCF 1.0E-6
> >      SCF_GUESS ATOMIC
> >      MAX_SCF 100
> >    &END SCF
> > #   &XC
> > #     &XC_FUNCTIONAL
> > #       &BECKE88
> > #         SCALE_X 0.95238
> > #       &END
> > #       &BECKE88_LR
> > #         OMEGA 0.33
> > #         SCALE_X -0.94979
> > #       &END
> > #       &LYP
> > #         SCALE_C 1.0
> > #       &END
> > #       &XALPHA
> > #         SCALE_X -0.13590
> > #       &END
> > #     &END XC_FUNCTIONAL
> > #     &HF
> > #      &SCREENING
> > #        EPS_SCHWARZ 1.0E-10
> > #        EPS_BOX 1.0E-10
> > #      &END
> > #      &MEMORY
> > #        MAX_MEMORY 500
> > #      &END
> > #      &INTERACTION_POTENTIAL
> > #        POTENTIAL_TYPE MIX_CL
> > #        OMEGA 0.33
> > #        SCALE_LONGRANGE 0.94979
> > #        SCALE_COULOMB 0.18352
> > #      &END
> > #     &END
> > #   &END XC
> > #
> > #   &XC
> > #     &XC_FUNCTIONAL Pade
> > #     &END XC_FUNCTIONAL
> > #   &END XC
> > #
> > #   &XC
> > #      &XC_FUNCTIONAL NONE
> > #      &END XC_FUNCTIONAL
> > #      &HF
> > #        &SCREENING
> > #          EPS_SCHWARZ 1.0E-6
> > #          EPS_BOX 1.0E-6
> > #          SCREEN_P_FORCES TRUE
> > #        &END
> > #        &MEMORY
> > #          MAX_MEMORY  2000
> > #        &END
> > #        &PERIODIC
> > #          NUMBER_OF_SHELLS 2
> > #        &END
> > #      &END
> > #   &END XC
> > #
> >    &XC
> >      &XC_FUNCTIONAL PBE0
> >      &END XC_FUNCTIONAL
> >      &HF
> >        &SCREENING
> >          EPS_SCHWARZ 1.0E-10
> >          EPS_BOX 1.0E-10
> >        &END
> >        &MEMORY
> >          MAX_MEMORY  2000
> >        &END
> >        &PERIODIC
> >          NUMBER_OF_SHELLS 4
> >        &END
> >      &END
> >    &END XC
> > #
> >  &END DFT
> >  &SUBSYS
> >    &CELL
> >      ABC 4.08 4.08 4.08
> >      UNIT ANGSTROM
> >      PERIODIC XYZ
> >    &END CELL
> >    &COORD
> >      Au 0.00  0.00  0.00
> >      Au 2.04  2.04  0.00
> >      Au 0.00  2.04  2.04
> >      Au 2.04  0.00  2.04
> >    &END COORD
> >    &KIND Au
> >      BASIS_SET TZ-GTH
> >      POTENTIAL GTH-PADE-q11
> >    &END KIND
> >  &END SUBSYS
> > &END FORCE_EVAL
> > &GLOBAL
> >  PROJECT Au4-rCAM-B3LYP
> >  PRINT_LEVEL MEDIUM
> >  RUN_TYPE ENERGY_FORCE
> > &END GLOBAL
>
> > Output:
>
> > CELL| Volume [ANGSTROM**3]:                                              67.917
> > CELL| Vector a [ANGSTROM]:       4.080     0.000     0.000    |a| =       4.080
> > CELL| Vector b [ANGSTROM]:       0.000     4.080     0.000    |b| =       4.080
> > CELL| Vector c [ANGSTROM]:       0.000     0.000     4.080    |c| =       4.080
> > CELL| Angle (b,c) [degree]:                                              90.000
> > CELL| Angle (a,c) [degree]:                                              90.000
> > CELL| Angle (a,b) [degree]:                                              90.000
> > CELL| Grid size for subcell generation                                    2.000
>
> > CELL_REF| Volume [ANGSTROM**3]:                                          67.917
> > CELL_REF| Vector a [ANGSTROM     4.080     0.000     0.000    |a| =       4.080
> > CELL_REF| Vector b [ANGSTROM     0.000     4.080     0.000    |b| =       4.080
> > CELL_REF| Vector c [ANGSTROM     0.000     0.000     4.080    |c| =       4.080
> > CELL_REF| Angle (b,c) [degree]:                                          90.000
> > CELL_REF| Angle (a,c) [degree]:                                          90.000
> > CELL_REF| Angle (a,b) [degree]:                                          90.000
> > CELL_REF| Grid size for subcell generation                                2.000
>
> > GENERATE|  Preliminary Number of Bonds generated:                             0
> > GENERATE|  Achieved consistency in connectivity generation.
> > GENERATE|  Number of Bonds generated:                                         0
> > GENERATE|  Preliminary Number of Bends generated:                             0
> > GENERATE|  Number of Bends generated:                                         0
> > GENERATE|  Number of UB generated:                                            0
> > GENERATE|  Preliminary Number of Torsions generated:                          0
> > GENERATE|  Number of Torsions generated:                                      0
> > GENERATE|  Number of Impropers generated:                                     0
> > GENERATE|  Number of 1-4 interactions generated:                              0
>
> > *******************************************************************************
> > *******************************************************************************
> > **                                                                           **
> > **     #####                         ##              ##                      **
> > **    ##   ##            ##          ##              ##                      **
> > **   ##     ##                       ##            ######                    **
> > **   ##     ##  ##   ##  ##   #####  ##  ##   ####   ##    #####    #####    **
> > **   ##     ##  ##   ##  ##  ##      ## ##   ##      ##   ##   ##  ##   ##   **
> > **   ##  ## ##  ##   ##  ##  ##      ####     ###    ##   ######   ######    **
> > **    ##  ###   ##   ##  ##  ##      ## ##      ##   ##   ##       ##        **
> > **     #######   #####   ##   #####  ##  ##  ####    ##    #####   ##        **
> > **           ##                                                    ##        **
> > **                                                                           **
> > **                                                ... make the atoms dance   **
> > **                                                                           **
> > **            Copyright (C) by CP2K Developers Group (2000 - 2008)           **
> > **                                                                           **
> > *******************************************************************************
>
> > DFT| Spin restricted Kohn-Sham (RKS) calculation                            RKS
> > DFT| Multiplicity                                                             1
> > DFT| Number of spin states                                                    1
> > DFT| Charge                                                                   0
> > DFT| Self-interaction correction (SIC)                                       NO
> > DFT| Cutoffs: density                                              1.000000E-10
> > DFT|          gradient                                             1.000000E-10
> > DFT|          tau                                                  1.000000E-10
> > DFT|          cutoff_smoothing_range                               0.000000E+00
> > DFT| XC density smoothing                                                  NONE
> > DFT| XC derivatives                                                          PW
> > FUNCTIONAL| ROUTINE=NEW
> > FUNCTIONAL| PBE:
> > FUNCTIONAL| J.P.Perdew, K.Burke, M.Ernzerhof, Phys. Rev. Letter, vol. 77, n 18,
> > FUNCTIONAL|  pp. 3865-3868, (1996)sx=0.750sc=1.000{spin unpolarized}
>
> > QS| Method:                                                                 GPW
> > QS| Density plane wave grid type                        NON-SPHERICAL FULLSPACE
> > QS| Number of grid levels:                                                    4
> > QS| Density cutoff [a.u.]:                                                100.0
> > QS| Multi grid cutoff [a.u.]: 1) grid level                               100.0
> > QS|                           2) grid level                                33.3
> > QS|                           3) grid level                                11.1
> > QS|                           4) grid level                                 3.7
> > QS| Grid level progression factor:                                          3.0
> > QS| Relative density cutoff [a.u.]:                                        25.0
> > QS| Consistent realspace mapping and integration
> > QS| Interaction thresholds: eps_pgf_orb:                                1.0E-05
> > QS|                         eps_core_charge:                            1.0E-12
> > QS|                         eps_rho_gspace:                             1.0E-10
> > QS|                         eps_rho_rspace:                             1.0E-10
> > QS|                         eps_gvg_rspace:                             1.0E-05
> > QS|                         eps_ppl:                                    1.0E-12
> > QS|                         eps_ppnl:                                   1.0E-12
>
> > ATOMIC KIND INFORMATION
>
> >  1. Atomic kind: Au                                    Number of atoms:       4
>
> >     Orbital basis set information for                                    TZ-GTH
>
> >       Number of orbital shell sets:
>
> ...
>
> read more ยป


More information about the CP2K-user mailing list