ABINIT Discussion Forums

Hi,
I am looking at WFs in Si near the Gamma point. For k-points very close to each other but in different directions, the character of the WF changes dramatically. I would expect the WF to evolve slowly and continuously as a function of k (within the same band) even in different directions, not abruptly like I see here. The WFs in question are both non-degenerate, so there is no freedom in choosing a linear combination of degenerate states so that the WF changes slowly. Can anyone explain this? The attached WFs (|\psi|) are in the second band at k28 = 0.0179 0.0179 0.0179 and k30 = 0.0000 0.0156 0.0156 in silicon. The WF at k30 looks very strange to me. For other bands, the WFs do change slowly and continuously from k28 --> k30. The attached files are .XSF files (I had to change the extension to upload them).
Thank you,
Marc Dvorak


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# Crystalline Silicon
# SCF Calculation

ecut 20



# Dataset 1
nband 10
toldfe 5.0d-12
nstep 50


kptopt 1
ngkpt 10 10 10
nshiftk 4
shiftk 0.5 0.5 0.5
0.5 0.0 0.0
0.0 0.5 0.0
0.0 0.0 0.5



# Structural Parameters

acell 3*7.25576
rprim 0.0000000000E+00 7.0710678119E-01 7.0710678119E-01
7.0710678119E-01 0.0000000000E+00 7.0710678119E-01
7.0710678119E-01 7.0710678119E-01 0.0000000000E+00
xred -1.0408340856E-17 -1.0408340856E-17 -1.0408340856E-17
2.5000000000E-01 2.5000000000E-01 2.5000000000E-01

ntypat 1
znucl 14

natom 2
typat 1 1


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# Crystalline Silicon
# non-SCF band structure calculation


ecut 20




# Dataset 1 - Non-SCF - get WF at n, k of interest
tolwfr 1.0d-19 # Convergence criteria
iscf -2 # Non-self-consistent
irdden 1 # Get density from Dataset 1
kptopt -5 # Read k-points directly
ndivk 28 32 11 1 35
kptbounds 0.5 0.5 0.5
0.0 0.0 0.0
0.0 0.5 0.5
0.25 0.625 0.625
0.375 0.75 0.375
0.0 0.0 0.0


nband 14 # Number of bands
nstep 1000 # 1000 minimization iterations - should converge much sooner
prtwf 1 # Print wave function





# Structural Parameters

acell 3*7.25576
rprim 0.0000000000E+00 7.0710678119E-01 7.0710678119E-01
7.0710678119E-01 0.0000000000E+00 7.0710678119E-01
7.0710678119E-01 7.0710678119E-01 0.0000000000E+00
xred -1.0408340856E-17 -1.0408340856E-17 -1.0408340856E-17
2.5000000000E-01 2.5000000000E-01 2.5000000000E-01

ntypat 1
znucl 14

natom 2
typat 1 1