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When generating the kpoint by vaspkit for two compounds that have the same lattice system, I found the kpath is G–X–S–Y–G–Z–U–R–T–Z|Y–T|U–X|S–R.

But why in the article (as shown in the picture) was a different path used? How is the correct path determined?

enter image description here enter image description here

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2 Answers 2

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There is no such thing as "correct path". The only condition you should use to select the path is that it has to be continuous, only that. After that, the selection will depend on what are you interesting in or what are you looking for. As the $\Gamma$ point is the center of the Brillouin zone, it is almost always used in the path.

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    $\begingroup$ No, you can not select the path U-$\Gamma$ because it is not continuous. $\endgroup$
    – Camps
    Feb 18, 2022 at 14:52
  • $\begingroup$ @Camps could you please clarify what you mean by the path U-$\Gamma$ not being continuous? $\endgroup$
    – ProfM
    Feb 19, 2022 at 10:57
  • $\begingroup$ Think as if you put your pencil in U and want to go straight to $\Gamma$, you cannot do that. You need to go to Z, then $\Gamma$ or go to X, then $\Gamma$ (these are the shorts path, but you can take a long one like U-R-T-Y-$\Gamma$). This will be reflected in a non continue electronic band. $\endgroup$
    – Camps
    Feb 20, 2022 at 19:47
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    $\begingroup$ @Camps I am not sure I follow. U and $\Gamma$ are two points, so I can always draw a straight line connecting them, right? $\endgroup$
    – ProfM
    Feb 20, 2022 at 20:19
  • $\begingroup$ @ProfM maybe a better explanation could be that the two points need to be directly connected by only one segment (in red color in the diagram). In this case, to go from U to $\Gamma$, if you go directly you are creating a "new" segment. $\endgroup$
    – Camps
    Feb 21, 2022 at 11:21
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Path U-Γ is not wrong, but it is illogical because they are very far from each other. Atoms in these two positions within the band will weakly interact with each other rather than interacting with X or Z. So you will likely find an abrupt change in band structure.

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