Author Topic: Query Regarding high symmetry points in band structure calculation  (Read 116 times)

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Offline harkishan_dua

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I have plotted the band structure of a tetragonal crystal lattice having space group symmetry p421m using ATK with unit cell dependent route (default route as given by the ATK VNL). In the band structure plot I have seen that the energy values for gamma and Z, R and X are same. In most cases for a tetragonal crystal lattice X, gamma, M and X points are only considered so I want to know, if I  do not consider R, X point  will it create any problem in band structure? What is the reason behind chosing of these high symmetry points (Z, R) for band structure?

Offline Troels-Markussen

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Hi,

You will never create problems in the bandstructure calculation by removing some high-symmetry points. The reason that (Gamma, Z)  and (X, R) have the same energy in your case is probably that you have a vacuum region in the z-direction. In this case, there is no interactions in the z-direction whereby the bands become flat. If this is not the case, then please share your script.

Regards,
Troels

Offline harkishan_dua

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Yes sir you are correct. I have kept a vacuum region in the z-direction however there is a buckling in my structure. 
Actually sir, I have communicated a paper by taking default route for band structure. However I have received a comment from the reviewer that  "On what basis authors have chosen the high symmetry points to plot phonon and electronic band
structures? As noticed from figure straight lines are observed in г-Z directions. For uniaxial strained band structure (Figure S2), they have used different high symmetry points. There is no clarity. "  So can you please suggest me how to defend this?
Thanking you

Offline Troels-Markussen

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Why not just leave out one of the points which have the same energy as another high-symmetry point. Did you know, that you can get a visual representation of the high-symmetry points using the Builder->Bulk Tools->Brillouin Zone Viewer.