Applying electric field

aarondesk aaro... at gmail.com
Wed Aug 11 21:51:02 CEST 2010


Hello,
  I am trying to apply an external electrical field to a DFT
(quickstep) calculation but am not having success. Please excuse my
ignorance. I have tried with a simple test molecule - CO - that I want
to apply an electrical field in the z direction.

  Below is my input (based off the regtest input).

  Unfortunately I get the same output whether the EFIELD section is
present or not, which leads me to believe that no external field is
being applied. Can you tell me what I'm doing wrong?

   Also, I have two other issues. The job crashes whenever START_STEP
is set to 0 ("On entry to DLASCL parameter number  4 had an illegal
value"), but 0 is the default value. Second, I don't quite understand
the units for the field intensity. Manual says W/cm2, but if I convert
this correctly, 5E15 W/cm2 = 3.77E11 V/angs which is huge.  I just
want an external field near 0.5 V/angs.

Thank you,
Aaron


&FORCE_EVAL
  METHOD Quickstep
  &DFT
    UKS
    BASIS_SET_FILE_NAME ./GTH_BASIS_SETS_5-12-10
    POTENTIAL_FILE_NAME ./GTH_POTENTIALS_5-12-10
    WFN_RESTART_FILE_NAME x-RESTART.wfn
    &MGRID
      CUTOFF 300
    &END MGRID
    &QS
      WF_INTERPOLATION ASPC
      EXTRAPOLATION_ORDER 3
    &END QS
    &SCF
     EPS_SCF 1.E-6
     SCF_GUESS RESTART
     MAX_SCF 400
     &OT T
       PRECONDITIONER FULL_SINGLE_INVERSE
       MINIMIZER DIIS
       LINESEARCH 3PNT
     &END OT
    &END SCF
    &XC
      &XC_FUNCTIONAL PBE
      &END XC_FUNCTIONAL
    &END XC
  &PRINT
  &END PRINT
  &EFIELD
       INTENSITY 5E15
       POLARISATION 0 0 1
       #WAVELENGTH 210
       ENVELOP CONSTANT
       &CONSTANT_ENV
         START_STEP 1
         END_STEP 20
       &END
  &END
  &END DFT
  &SUBSYS
    &CELL
      ABC 8.965 8.965 8.965
    &END CELL
    &COORD
     SCALED F
C 0.0 0.0 0.0
O 0.0 0.0 1.13
    &END COORD
    &KIND O
      BASIS_SET TZVP-MOLOPT-GTH
      POTENTIAL GTH-PBE-q6
    &END KIND
    &KIND C
      BASIS_SET TZVP-MOLOPT-GTH
      POTENTIAL GTH-PBE-q4
    &END KIND
    &END SUBSYS
&END FORCE_EVAL
&GLOBAL
  PROJECT CO
  RUN_TYPE GEO_OPT
  PRINT_LEVEL LOW
&END GLOBAL
 &MOTION
  &GEO_OPT
    MAX_ITER 200
    MAX_FORCE 0.0009725
    OPTIMIZER BFGS
  &END GEO_OPT



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