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syml.foobar ​

Symmetry line for the band plot. We can generate syml.foobar by getsyml.

Get symmetry lines for band plot and Brillouwin zone plot. ​

syml.* is generated from ctrl.*. syml.* is needed for band plot. After generated, you can easily edit syml.* for job_band.

At ecalj/GetSyml, we have getsyml.py, which is based on the seekpath at https://github.com/giovannipizzi/seekpath/ and spglib at https://anaconda.org/conda-forge/spglib

Usage: ​

We make softlink getsyml to ecalj/SRC/GetSyml/getsyml.py during the install by InstallAll.py. Run

getsyml nio
(or)
getsyml ctrls.nio

. This show 3D Brillouin zone together with symmetry lines for band plot. See BZsamples here. The symmetry lines are written into the syml.* file for ecalj. The number of divisions for syml is give by a crude algorism, so edit it if necessary.

Needed citations for getsyml ​

In addition to usual ecalj acknowledgement, following citations are required when you make a publication.

1.Y. Hinuma, G. Pizzi, Y. Kumagai, F. Oba, I. Tanaka, Band structure diagram paths based on crystallography, Comp. Mat. Sci. 128, 140 (2017)

2.You should also cite spglib that is an essential library used in the implementation. https://github.com/atztogo/spglib.git

  • See Lincence.txt for spglib and seekpath.

(memo for developer) ​

a.Modify lmchk to write required information to supply reasonable. For example, ndiv (mesh size along lines). b.Numerical accuracy of calculations. np.set_printoptions(precision=16) is not meaningful since we read output of lmchk

symmetry-line file : input for plotting energy bands along selected symmetry lines or for generating constant-energy contours such as a Fermi surface. This file (whose name is specified as a modifier with the command-line argument --band, described in the "Command-line switches" section) can take on of several forms.

format of syml ​

generate bands along specific symmetry lines.
The following sample input illustrates input for lines
X->Gamma and Gamma->M for the simple cubic lattice.
   21  .5 0  0    0  0  0         X     Gamma
   21  0  0  0    .5 .5 0         Gamma  M
   0   0  0  0    0  0  0
The first number designates how many points along each line.
The next six label the starting and ending q-points,
respectively.  Note that the last line must contain zeros.