Mulliken charge problem

obo bo... at matcalc.de
Tue Aug 11 11:10:35 CEST 2009


thank you!
these Basis Sets works better. the error with the poisson and the
cholesky error is vanished.
but I think the relaxation of the cell is still wrong. after
relaxation of the hexagonal cell, the two vector have not the same
length. with the pbe functional the lengths are only a=4.816 b=4.818
aangstrom and with the BLYP 4.845 and 4.847!!!
The biggest variation is in the O-Si-O angles, which range from 105°
to 115°!
The problem with the orthorhombic cell is still present. The relation
b=3^0.5*a is not fulfilled and so the Mulliken charges are also wrong.
For example I've got the following charges:

  Atom     |    Charge

     1  Si    0.957166
     2  Si    0.955747
     3  Si    0.919798
     4  O    -0.467908
     5  O    -0.488780
     6  O    -0.459461
     7  O    -0.473715
     8  O    -0.454923
     9  O    -0.487922
    10  Si    0.957148
    11  Si    0.955763
    12  Si    0.919796
    13  O    -0.467886
    14  O    -0.488787
    15  O    -0.459514
    16  O    -0.473733
    17  O    -0.454871
    18  O    -0.487918
  Total       0.000000

On 10 Aug., 09:11, Matthias <matthia... at psi.ch> wrote:
> cp2k/tests/QS/BASIS_MOLOPT
>
> Matthias
>
> On Aug 10, 9:05 am, obo <bo... at matcalc.de> wrote:
>
> > thanks for your answer.
> > do you know where i can download a BASIS SET file with these MOLOPT
> > basis sets?
>
> > Oliver
>
> > On 10 Aug., 09:01, Matthias <matthia... at psi.ch> wrote:
>
> > > The overlap matrix for such basis sets becomes ill-conditioned. Please
> > > note, augmented basis sets as employed for molecular systems are
> > > usually not suited for condensed systems and shouldn't be used for
> > > such systems. You may try the MOLOPT basis sets e.g. DZVP-MOLOPT-SR-
> > > GTH-q4 for Si and DZVP-MOLOPT-SR-GTH-q6 for O for your quartz systems.
>
> > > Matthias
>
> > > On Aug 10, 8:39 am, obo <bo... at matcalc.de> wrote:
>
> > > > I have tested different Basis Sets. With confined Basis Sets the
> > > > problem becomes better but there is a difference anymore.
> > > > With an augment Basis Set I get the following error:
>
> > > >  *** 08:35:30 ERRORL2 in cp_fm_cholesky:cp_fm_cholesky_decompose
> > > > err=-300   ***
> > > >  *** condition FAILED at line 92
>
> > > > I have reada about linear dependences in the BASIS SET. Can somebody
> > > > explain me what this means?
> > > > thanks
> > > > Oliver
>
> > > > On 3 Aug., 10:23, obo <bo... at matcalc.de> wrote:
>
> > > > > Dear cp2k Users,
> > > > > I've made some calculations with alpha quarz. At first I have
> > > > > optimized the hexagonal cell with 9 atoms. I've got the initial
> > > > > coordinates from a cell optimization in another ab initio programm.
> > > > > The relaxation in cp2k was sucessfull and the mulliken charges from
> > > > > the Si atoms are approximately the same. Now I have constructed an
> > > > > orthorhombic cell with 19 atoms. I've constructed the basis from the
> > > > > coordinates of the relaxed hexagonal cell. The length of the cell
> > > > > vectors are also calculated from the hexagonal cell vectors(a, 3^0.5,
> > > > > c).
> > > > > When I start the cell optimization, I get the following mulliken
> > > > > charges:
> > > > >   Atom     |    Charge
> > > > >      1  Si    1.370421
> > > > >      2  Si    1.349422
> > > > >      3  Si    0.726644
> > > > >      4  O    -0.611734
> > > > >      5  O    -0.644209
> > > > >      6  O    -0.595641
> > > > >      7  O    -0.609976
> > > > >      8  O    -0.586622
> > > > >      9  O    -0.647799
> > > > >     10  Si    1.473611
> > > > >     11  Si    1.489633
> > > > >     12  Si    0.829598
> > > > >     13  O    -0.609031
> > > > >     14  O    -0.568553
> > > > >     15  O    -0.591643
> > > > >     16  O    -0.610546
> > > > >     17  O    -0.600818
> > > > >     18  O    -0.562758
> > > > >   Total       0.000000
>
> > > > > At the end of the cell optimization, the relation between the cell
> > > > > vectors (a and 3^0.5*a) are also wrong.
> > > > > What is my mistake??? Can somebody help me?
>
> > > > > The input file:
>
> > > > > &FORCE_EVAL
> > > > >   METHOD Quickstep
> > > > >   STRESS_TENSOR NUMERICAL
> > > > >   &DFT
> > > > >      &POISSON
> > > > >        PERIODIC XYZ
> > > > >        POISSON_SOLVER PERIODIC
> > > > >        &EWALD
> > > > >         EWALD_TYPE SPME
> > > > >        &END
> > > > >      &END POISSON
> > > > >     &MGRID
> > > > >       CUTOFF 650
> > > > >       RELATIVE_CUTOFF 85.0
> > > > >     &END MGRID
> > > > >     &QS
> > > > >      WF_INTERPOLATION PS
> > > > >      EXTRAPOLATION_ORDER 4
> > > > >     &END QS
> > > > >     &SCF
> > > > >       EPS_SCF 1.E-6
> > > > >       CHOLESKY OFF
> > > > >       MAX_SCF 50
> > > > >       SCF_GUESS ATOMIC
> > > > >       &OUTER_SCF
> > > > >         DIIS_BUFFER_LENGTH 5
> > > > >         OPTIMIZER DIIS
> > > > >       &END OUTER_SCF
> > > > >     &END SCF
> > > > >     &XC
> > > > >        &XC_GRID
> > > > >         XC_DERIV SPLINE3
> > > > >        &END XC_GRID
> > > > >        &XC_FUNCTIONAL PBE
> > > > >        &END XC_FUNCTIONAL
> > > > >     &END XC
> > > > >   &END DFT
> > > > >   &SUBSYS
> > > > >     &CELL
> > > > >       PERIODIC XYZ
> > > > >       MULTIPLE_UNIT_CELL 1 1 1
> > > > >       ABC 4.805 8.3225 5.393
> > > > >       ALPHA_BETA_GAMMA  90.0 90.0 90.0
> > > > >     &END CELL
> > > > >     &COORD
> > > > > Si 1.1328078594000004 6.4061604696       3.5954303785000006
> > > > > Si 1.1329589190000002 1.9039591092000003 1.7978168006000006
> > > > > Si 2.6289910789000004 8.3163249591       5.3929132817
> > > > > O 1.6426232969999999  7.8451213509999995 4.154876766399999
> > > > > O 4.4371215705        1.6255884538000005 2.3576057410000004
> > > > > O 3.6202186447        7.155568958499999  0.5597043610000001
> > > > > O 1.6427913173999997  0.4650789015000002 1.237976828999999
> > > > > O 3.620111714099999   1.1547964305000002 4.8334310334
> > > > > O 4.4368490245        6.684213627799998  3.035570217399999
> > > > > Si 3.4358078594       2.2346604696       3.5954303785000006
> > > > > Si 3.435958918999999  6.054959109200001  1.7978168006000006
> > > > > Si 0.1269910789       4.144824959099999  5.3929132817
> > > > > O 3.9456232970000005  3.6736213510000013 4.154876766399999
> > > > > O 1.9351215704999998  5.776588453800002  2.3576057410000004
> > > > > O 1.1182186447000002  2.984068958500001  0.5597043610000001
> > > > > O 3.9457913174000008  4.616078901500002  1.237976828999999
> > > > > O 1.1181117141        5.305796430500002  4.8334310334
> > > > > O 1.9348490245        2.5127136278000006 3.035570217399999
> > > > >      &END COORD
> > > > >     &KIND Si
> > > > >       BASIS_SET DZVP-GTH-PBE
> > > > >       POTENTIAL GTH-PBE-q4
> > > > >     &END KIND
> > > > >     &KIND O
> > > > >       BASIS_SET DZVP-GTH-PBE
> > > > >       POTENTIAL GTH-PBE-q6
> > > > >     &END KIND
> > > > >     &KIND H
> > > > >       BASIS_SET DZVP-GTH-PBE
> > > > >       POTENTIAL GTH-PBE-q1
> > > > >     &END KIND
> > > > >     &TOPOLOGY
> > > > >      CENTER_COORDINATES T
> > > > >      &DUMP_PDB
> > > > >      &END
> > > > >        MULTIPLE_UNIT_CELL 1 1 1
> > > > >     &END TOPOLOGY
> > > > >   &END SUBSYS
> > > > > &END FORCE_EVAL
> > > > > &GLOBAL
> > > > >   PROJECT SiO-Cell
> > > > >   RUN_TYPE CELL_OPT
> > > > >   PRINT_LEVEL MEDIUM
> > > > > &END GLOBAL
> > > > > &MOTION
> > > > >   &GEO_OPT
> > > > >   MAX_ITER 200
> > > > >   OPTIMIZER BFGS
> > > > >   MAX_FORCE 5.0E-5
> > > > >   &END GEO_OPT
> > > > >   &CELL_OPT
> > > > >    EXTERNAL_PRESSURE [bar] 0.0
> > > > >    PRESSURE_TOLERANCE 15.0
> > > > >    MAX_ITER 900
> > > > >    KEEP_ANGLES TRUE
> > > > >    OPTIMIZER CG
> > > > >    &CG
> > > > >     &LINE_SEARCH
> > > > >       TYPE 2PNT
> > > > >     &END LINE_SEARCH
> > > > >    &END CG
> > > > >   &END CELL_OPT
> > > > > &END MOTION
>
> > > > > thanks
> > > > > Oliver
>
>


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