A strange problem about hybrid-DFT combined with all-electron calculation

Igor Ying Zhang wenx... at gmail.com
Mon Dec 27 04:15:33 CET 2010


Dear all:

     I am a beginner here. I started learning CP2K by investigating 6
cases in gas without periodic bondary condition which I had done in
the Gaussian03 package (G03). These cases contains CH4, C2H6, C6H14,
C8H18, C32H66, and C60. All of these calculations were performed at
the theoretical level of B3LYP/6-311G** without pesudopotential. I am
very happy to see that CP2K leads to very close results to G03 for
CH4, C2H6, C8H18, and C60. The deviations between each other are less
than 1.0E-5 (CH4), 1.0E-4 (C2H6), 1.0E-4 (C6H14), 1.0E-4 (C8H18) and
1.0E-3 a.u. (C60). However, the deviation for C32H66 is more than 5.0
a.u., where the input statement is the same as the other 5 examples.

     For C32H66, the computed total energy from G03 is -1259.58294069
a.u., which is about -1264.57308160 a.u. with the cell size of
18x55x18, and -1264.65816635 a.u. with 25x55x25, and -1264.65985171
a.u. with 25x60x25. The deviations are very huge. And another puzzling
thing is that when I choose the cell size of 22x60x22, the total
energy obtained from CP2K is about -1260.48059560 a.u. which has the
deviation of more than 4 a.u. against results of the other three cell
size.

      The input file of C32H66 is:

@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
&FORCE_EVAL
  METHOD Quickstep
  &DFT
    BASIS_SET_FILE_NAME /share/apps/cp2k/tests/QS/EMSL_BASIS_SETS
    POTENTIAL_FILE_NAME /share/apps/cp2k/tests/QS/POTENTIAL
    &MGRID
      CUTOFF 300
      REL_CUTOFF 50
    &END MGRID
    &QS
      METHOD GAPW
      EPS_FILTER_MATRIX 1.0E-32
      EPS_PGF_ORB       1.0E-32
    &END QS
    &POISSON
      PERIODIC NONE
      PSOLVER ANALYTIC
    &END
    &SCF
      EPS_SCF 1.0E-5
      SCF_GUESS RESTART
      MAX_SCF 30
      &OT T
          PRECONDITIONER FULL_ALL
          ENERGY_GAP     0.001
          LINESEARCH     2PNT
          MAX_TAYLOR     5
          MINIMIZER      DIIS
          STEPSIZE       0.2
      &OUTER_SCF
          EPS_SCF 1.0E-5
          MAX_SCF 20
      &END OUTER_SCF
    &END SCF
    &XC
      &XC_FUNCTIONAL
       &LYP
         SCALE_C 0.81
       &END
       &BECKE88
         SCALE_X 0.72
       &END
       &VWN
         FUNCTIONAL_TYPE VWN3                 # VWN3 is employed as in
Gaussian package
         SCALE_C 0.19
       &END
       &XALPHA
         SCALE_X 0.08
       &END
      &END XC_FUNCTIONAL
      &HF
          FRACTION 0.20
          &MEMORY
              MAX_MEMORY 800                          # The memory
available to one MPI process.
              EPS_STORAGE_SCALING 1.0E-1
          &END MEMORY
          &SCREENING
              EPS_SCHWARZ 1.0E-8
              #SCREEN_ON_INITIAL_P FALSE
          &END SCREENING
          #&INTERACTION_POTENTIAL
          #    POTENTIAL_TYPE TRUNCATED
          #   CUTOFF_RADIUS 15.000
          #    T_C_G_DATA /share/apps/cp2k/tests/QS/t_c_g.dat
          #&END INTERACTION_POTENTIAL
      &END HF
    &END XC
  &END DFT
  &SUBSYS
    &CELL
      ABC  22.0 60.0 22.0
      PERIODIC NONE
    &END CELL
    &COORD
C      1.14606000     41.16159800      1.38290300
C      1.99581200     39.88741400      1.38290300
C      1.16086200     38.60168100      1.38290300
C      2.00192600     37.32025900      1.38290300
C      1.16543600     36.03559700      1.38290300
C      2.00613200     34.75370300      1.38290300
C      1.16894800     33.46950900      1.38290300
C      2.00897600     32.18717100      1.38290300
C      1.17120900     30.90335100      1.38290300
C      2.01068900     29.62065000      1.38290300
C      1.17244700     28.33713700      1.38290300
C      2.01150800     27.05416000      1.38290300
C      1.17291300     25.77087700      1.38290300
C      2.01168800     24.48771200      1.38290300
C      1.17287900     23.20456800      1.38290300
C      2.01150800     21.92130700      1.38290300
C      1.17262600     20.63820900      1.38290300
C      2.01125500     19.35494800      1.38290300
C      1.17244600     18.07180400      1.38290300
C      2.01122100     16.78863900      1.38290300
C      1.17262600     15.50535600      1.38290300
C      2.01168700     14.22237900      1.38290300
C      1.17344500     12.93886600      1.38290300
C      2.01292500     11.65616500      1.38290300
C      1.17515800     10.37234500      1.38290300
C      2.01518600      9.09000700      1.38290300
C      1.17800200      7.80581300      1.38290300
C      2.01869800      6.52391900      1.38290300
C      1.18220800      5.23925700      1.38290300
C      2.02327200      3.95783500      1.38290300
C      1.18832200      2.67210200      1.38290300
C      2.03807400      1.39791800      1.38290300
H      1.77043400     42.05951600      1.38290300
H      0.50042500     41.20620200      2.26580600
H      0.50042500     41.20620200      0.50000000
H      2.65562800     39.88856000      2.25915700
H      2.65562800     39.88856000      0.50664900
H      0.50000000     38.60136000      0.50611800
H      0.50000000     38.60136000      2.25968800
H      2.66253300     37.32153700      2.25970500
H      2.66253300     37.32153700      0.50610100
H      0.50479700     36.03454000      0.50615900
H      0.50479700     36.03454000      2.25964700
H      2.66674500     34.75460500      2.25967700
H      2.66674500     34.75460500      0.50612900
H      0.50830200     33.46878500      0.50615100
H      0.50830200     33.46878500      2.25965500
H      2.66959500     32.18775000      2.25967600
H      2.66959500     32.18775000      0.50613000
H      0.51056300     30.90291600      0.50614800
H      0.51056300     30.90291600      2.25965800
H      2.67131300     29.62096400      2.25967400
H      2.67131300     29.62096400      0.50613200
H      0.51180300     28.33692900      0.50614600
H      0.51180300     28.33692900      2.25966000
H      2.67213500     27.05427600      2.25967200
H      2.67213500     27.05427600      0.50613400
H      0.51227200     25.77083400      0.50614400
H      0.51227200     25.77083400      2.25966200
H      2.67231900     24.48770200      2.25966900
H      2.67231900     24.48770200      0.50613700
H      0.51224100     23.20461800      0.50614200
H      0.51224100     23.20461800      2.25966400
H      2.67214200     21.92124000      2.25966700
H      2.67214200     21.92124000      0.50613900
H      0.51199200     20.63827600      0.50613900
H      0.51199200     20.63827600      2.25966700
H      2.67189300     19.35489800      2.25966400
H      2.67189300     19.35489800      0.50614200
H      0.51181500     18.07181400      0.50613700
H      0.51181500     18.07181400      2.25966900
H      2.67186200     16.78868200      2.25966200
H      2.67186200     16.78868200      0.50614400
H      0.51199900     15.50524000      0.50613400
H      0.51199900     15.50524000      2.25967200
H      2.67233100     14.22258700      2.25966000
H      2.67233100     14.22258700      0.50614600
H      0.51282100     12.93855200      0.50613200
H      0.51282100     12.93855200      2.25967400
H      2.67357100     11.65660000      2.25965800
H      2.67357100     11.65660000      0.50614800
H      0.51453900     10.37176600      0.50613000
H      0.51453900     10.37176600      2.25967600
H      2.67583200      9.09073100      2.25965500
H      2.67583200      9.09073100      0.50615100
H      0.51738900      7.80491100      0.50612900
H      0.51738900      7.80491100      2.25967700
H      2.67933700      6.52497600      2.25964700
H      2.67933700      6.52497600      0.50615900
H      0.52160100      5.23797900      0.50610100
H      0.52160100      5.23797900      2.25970500
H      2.68413400      3.95815600      2.25968800
H      2.68413400      3.95815600      0.50611800
H      0.52850600      2.67095600      0.50664900
H      0.52850600      2.67095600      2.25915700
H      1.41370000      0.50000000      1.38290300
H      2.68370900      1.35331400      2.26580600
H      2.68370900      1.35331400      0.50000000
    &END COORD
    &KIND C
      BASIS_SET 6-311G**
      POTENTIAL ALL
    &END KIND
    &KIND H
      BASIS_SET 6-311G**
      POTENTIAL ALL
    &END KIND
  &END SUBSYS
&END FORCE_EVAL

&GLOBAL
  PROJECT C32H66
  RUN_TYPE ENERGY
  PRINT_LEVEL MEDIUM
&END GLOBAL
@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@

And in the output file, I got the warning message as follow:
@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
 *** 00:05:54 WARNING in
hfx_energy_potential:integrate_four_center        ***
 *** err=-300  The Kohn Sham matrix is not 100% occupied. This may
result  ***
 *** in uncorrect Hartree-Fock results. Try to decrease EPS_PGF_ORB
and    ***
 *** EPS_FILTER_MATRIX in the QS
section.                                  ***
@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@

I have decreased EPS_PGF_ORB and EPS_FILTER_MATREX, and also employed
truncated coulomb
interaction as suggested from the old post (http://groups.google.com/
group/cp2k/browse_thread/thread/1959ddee999d3a8e/6fae4716f12cd538?
lnk=raot&fwc=1)


      Any suggestions are welcome. Best wishes!


Igor Ying Zhang


More information about the CP2K-user mailing list