[DFTB-Plus-User] DOS Fermi Energy problem

[Ezgi Erdogan]

Dear users,
I would like to ask you the density of states (DOS) graphics. I have trouble
around fermi level.

1- Proper Density and Unitcell Geometry
a) dftb_in_dos.hsd input file is:
///////////////////////////////////////////////
Geometry = GenFormat {
<<<"dftb_in.geometry.gen"
}

Hamiltonian = DFTB {
  SCC = No
  SCCTolerance = 1e-5
  MaxAngularMomentum = {
    C = "p"
    H = "s"
  }
 SlaterKosterFiles = {
    C-C = ""
    C-H = ""
    H-C = ""
    H-H = ""

   }
PolynomialRepulsive = SetForAll{No}

  KPointsAndWeights = SupercellFolding {
    8   0     0
    0   1     0
    0   0     1
    0.5 0.0  0.0
  }
}


b) dftb_in_dos.geometry.gen
///////////////////////////////////////////
For Density of State calculation we have to shift our geometry to Unitcell.
 28  S
  C  H
    1 2      0.98140000      1.04655000      0.00000000
    2 1      1.54350100      1.97980000      0.00000000
    3 1      0.85434800      3.22200000      0.00000000
    4 1      1.52784100      4.44910000      0.00000000
    5 1      0.83841700      5.70995000      0.00000000
    6 1      1.52558700      6.93745000      0.00000000
    7 1      0.85861600      8.16790000      0.00000000
    8 1      1.55011300      9.44240000      0.00000000
    9 1      0.88311300     10.67285000      0.00000000
   10 1      1.56219600     11.92150000      0.00000000
   11 1      0.86961700     13.18065000      0.00000000
   12 1      1.52639800     14.42235000      0.00000000
   13 1      0.76925600     15.62445000      0.00000000
   14 2      1.44626500     16.47830000      0.00000000
   15 2      3.49406700      1.00195000      0.00000000
   16 1      2.96557000      1.95460000      0.00000000
   17 1      3.69848600      3.17155000      0.00000000
   18 1      3.00933300      4.41370000      0.00000000
   19 1      3.70284500      5.69035000      0.00000000
   20 1      3.02619500      6.93325000      0.00000000
   21 1      3.69503000      8.16930000      0.00000000
   22 1      3.00756000      9.44100000      0.00000000
   23 1      3.67642400     10.67705000      0.00000000
   24 1      2.99974500     11.91995000      0.00000000
   25 1      3.68177400     13.20275000      0.00000000
   26 1      3.00338200     14.40000000      0.00000000
   27 1      3.60368600     15.68735000      0.00000000
   28 2      2.82484200     16.44975000      0.00000000
       0.00000000      0.00000000      0.00000000
     5.009544167      0.00000000      0.00000000
      0.00000000     50.00000000      0.00000000
      0.00000000      0.00000000     50.00000000


2- Run this input and geometry.

    Look for Fermi Energy Level.
Fermi energy:                    -0.1837716172 H       -5.000680 eV
 Band energy:                    -43.6825057076 H    -1188.661459 eV
 TS:                               0.0000000000 H        0.000000 eV
 Band free energy (E-TS):        -43.6825057076 H    -1188.661459 eV
 Extrapolated E(0K):             -43.6825057076 H    -1188.661459 eV


 Energy H0:                        0.0000000000 H        0.000000 eV
 Total Electronic energy:        -43.6825057076 H    -1188.661459 eV
 Repulsive energy:                 1.4070475536 H       38.287712 eV
 Total energy:                   -42.2754581540 H    -1150.373747 eV
 Total Mermin free energy:       -42.2754581540 H    -1150.373747 eV

 Calculation with static geometry

 Non-SCC calculation


2- For proper dos.dat plotting we have to use 2 scripts :

 band2dat and dosplot.in


a)  band2dat -N dftb_in_dos.band.out band.dat
b)   for dosplot in:

 [gauss]
coefficient = 0.2
exponent = 20.0
[data]
nr_kpoints = 50   #change this which k point you want to calculate
kweights =  1.000000

eigenvalues = << dftb_in_dos.dat
eigval_order = k_major

 dosplot dosplot.in > dos.dat      if you run from your folder "bin"

3-  and to plot:
xmgrace dos.dat

Now here is my question is coming. In this geometry there should be confused
Fermi Energy Level or I am calculating in wrong way? So which Fermi Energy
Level in this DOS graphics should be done. From detailed.out file we can
say:  Fermi energy: -0.1837716172 H       -5.000680 eV. To shift +Efermi
Level or -Efermi Level or just draw this plot between -4  to 4 or what could
be other solution? For my further calculation I have to get proper Fermi
Energy Level and DOS graphs.

Thank you for support

Ezgi
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