Hi Dan, Rui ran into the same problem before. Sometimes Mulliken population is tricky. If Hirshfeld and Voronoi charge agree with each other, trust these two methods.
Best wishes, Shen On Fri, Oct 6, 2017 at 10:13 AM, Dan Gil <[email protected]> wrote: > Hi, > > I am using Siesta 3.2 and ran into a strange problem. > > I simulate a water molecule and the Mulliken charges are wrong. It shows > that the oxygen atom is positively charged and the two hydrogens are > negatively charged. The Hirshfeld and Voronoi populations are fine. Did I > run into a bug? > > *input.fdf* > NumberOfAtoms 3 > NumberOfSpecies 4 > > %block ChemicalSpeciesLabel > 1 13 Al > 2 14 Si > 3 8 O > 4 1 H > %endblock ChemicalSpeciesLabel > > PAO.BasisType nodes > > %block PAO.BasisSizes > Al DZP > Si DZP > O DZP > H DZP > %endblock PAO.BasisSizes > > XC.functional GGA > XC.authors PBE > > # SCF options > MaxSCFIterations 200 > DM.MixingWeight 0.25 # New DM amount for next SCF cycle > DM.Tolerance 1.d-6 # Tolerance in maximum difference > SolutionMethod diagon # OrderN or Diagon > MeshCutoff 400 Ry > DM.Require.Energy.Convergence .true. > DM.Energy.Tolerance 1.d-6 eV > > MD.TypeOfRun CG > MD.NumCGsteps 100 > MD.InitialTemperature 300.0 K > MD.TargetTemperature 300.0 K > > WriteHirshfeldPop .true. > WriteVoronoiPop .true. > WriteMullikenPop 1 > > LatticeConstant 1 Ang > > %block LatticeVectors > 9.5160000000 0.0000000000 0.0000000000 > -4.7580000000 8.2411000000 0.0000000000 > 0.0000000000 0.0000000000 48.2792733630 > %endblock LatticeVectors > > WarningMinimumAtiomicDistance 1.0 Ang > AtomicCoordinatesFormat NotScaledCartesianAng > %block AtomicCoordinatesAndAtomicSpecies < Coord.fdf > > *Coord.fdf* > 5.265981 -1.943725 -6.378528 3 > 4.222545 -1.943725 -6.378528 4 > 5.612381 -0.997652 -6.378528 4 > > *Output (excerpts)* > mulliken: Mulliken Atomic and Orbital Populations: > Species: O > Atom Qatom Qorb > 2s 2s 2py 2pz 2px 2py 2pz > 2px > 2Pdxy 2Pdyz 2Pdz2 2Pdxz 2Pdx2-y2 > 1 5.764 1.436 -0.027 1.363 1.793 1.235 -0.023 -0.003 -0.034 > 0.003 0.002 0.005 0.001 0.014 > > Species: H > Atom Qatom Qorb > 1s 1s 1Ppy 1Ppz 1Ppx > 2 1.118 0.845 0.036 0.063 0.104 0.070 > 3 1.118 0.845 0.036 0.091 0.104 0.042 > > Hirshfeld Net Atomic Populations: > Atom # Qatom Species > 1 -0.234 O > 2 0.117 H > 3 0.117 H > > Voronoi Net Atomic Populations: > Atom # Qatom Species > 1 -0.171 O > 2 0.086 H > 3 0.085 H > > Best Regards, > > Dan > > >
