[Wien] problems on boundary between muffin tin and interstitial

[simon.kurasch@uni-ulm.de]

Dear Prof. Blaha and all other Wien2k users

I want to calculate the electrostatic potential of BN.
I was making linescans of clmsum and vcoul (different directions  
always starting from a core position) before and after SCF.
In some directions the curves do not match in value nor slope on the  
boarder of the muffin tin.
It seems like the SCF has no influence because the linescans from the  
starting density already showed jumps on the boarder.

I was setting up the struct file using structgen
    -> H   LATTICE,NONEQUIV.ATOMS:  2187_P-6m2
I used gga -6Ry and performed non spin polarized and spin polarized  
calculations.

I varied separation energy, rmts, rkmax, gmax and readjusted  
linearization energies but could not solve the problem.
Adding or removing local orbitals had a strong influence but I don't  
have any experience in doing that. I just did that by try and error.

For testing I changed the struct file to CXZ LATTICE,NONEQUIV.ATOMS:   
2 but had similar problems.

I hope anyone can give me a hint what I'm making wrong.

yours sincerely
Simon Kurasch



First I started with this struct file:
Boron Nitride
H   LATTICE,NONEQUIV.ATOMS:  2187_P-6m2
MODE OF CALC=RELA unit=ang
   4.667625  4.667625 18.897269 90.000000 90.000000120.000000
ATOM  -1: X=0.66666666 Y=0.33333333 Z=0.50000000
           MULT= 1          ISPLIT= 4
B 1        NPT=  781  R0=0.00010000 RMT=    1.3400   Z:  5.0
LOCAL ROT MATRIX:    1.0000000 0.0000000 0.0000000
                      0.0000000 1.0000000 0.0000000
                      0.0000000 0.0000000 1.0000000
ATOM  -2: X=0.33333333 Y=0.66666666 Z=0.50000000
           MULT= 1          ISPLIT= 4
N 1        NPT=  781  R0=0.00010000 RMT=    1.3400   Z:  7.0
LOCAL ROT MATRIX:    1.0000000 0.0000000 0.0000000
                      0.0000000 1.0000000 0.0000000
                      0.0000000 0.0000000 1.0000000
   12      NUMBER OF SYMMETRY OPERATIONS

Later I changed to this one:
Title
CXZ LATTICE,NONEQUIV.ATOMS:  2
MODE OF CALC=RELA unit=bohr
   8.085213 20.406413  4.668000 90.000000 90.000000112.181683
ATOM  -1: X=0.00000000 Y=0.00000000 Z=0.00000000
           MULT= 1          ISPLIT= 8
N 1        NPT=  781  R0=0.00010000 RMT=    1.3400   Z:  7.0
LOCAL ROT MATRIX:    1.0000000 0.0000000 0.0000000
                      0.0000000 1.0000000 0.0000000
                      0.0000000 0.0000000 1.0000000
ATOM  -2: X=0.33333333 Y=0.00000000 Z=0.00000000
           MULT= 1          ISPLIT= 8
B 1        NPT=  781  R0=0.00050000 RMT=    1.3400   Z:  5.0
LOCAL ROT MATRIX:    1.0000000 0.0000000 0.0000000
                      0.0000000 1.0000000 0.0000000
                      0.0000000 0.0000000 1.0000000
    2      NUMBER OF SYMMETRY OPERATIONS
  1 0 0 0.00000000
  0 1 0 0.00000000
  0 0 1 0.00000000
        1
  1 0 0 0.00000000
  0 1 0 0.00000000
  0 0-1 0.00000000
        2

default case.in1:
WFFIL        (WFPRI, SUPWF)
   7.00       10    4 (R-MT*K-MAX; MAX L IN WF, V-NMT
   0.30    3  0      (GLOBAL E-PARAMETER WITH n OTHER CHOICES, global APW/LAPW)
  0   -1.16      0.002 CONT 1
  0    0.30      0.000 CONT 1
  1    0.30      0.000 CONT 1
   0.30    2  0      (GLOBAL E-PARAMETER WITH n OTHER CHOICES, global APW/LAPW)
  0    0.30      0.000 CONT 1
  1    0.30      0.000 CONT 1
K-VECTORS FROM UNIT:4   -9.0       2.0    14   emin/emax/nband