Dear All, I have performed Z₂ invariant calculations for Bi₂Se₃ using WannierTools (with VASP). For reference, I followed the example provided in the official documentation: https://wannier-tools.readthedocs.io/en/latest/tutorials/Bi2Se3.html In that example, the Z₂ invariants for the six time-reversal invariant momentum (TRIM) planes are reported as:
k₁ = 0.0, k₂-k₃ plane: z₂ = 1 k₁ = 0.5, k₂-k₃ plane: z₂ = 0 k₂ = 0.0, k₁-k₃ plane: z₂ = 1 k₂ = 0.5, k₁-k₃ plane: z₂ = 0 k₃ = 0.0, k₁-k₂ plane: z₂ = 1 k₃ = 0.5, k₁-k₂ plane: z₂ = 0 However, in my case, using the same POSCAR file from the tutorial (https://github.com/quanshengwu/wannier_tools) and following the same procedure, I obtained: k₁ = 0.0, k₂-k₃ plane: z₂ = 1 k₁ = 0.5, k₂-k₃ plane: z₂ = 0 k₂ = 0.0, k₁-k₃ plane: z₂ = 1 k₂ = 0.5, k₁-k₃ plane: z₂ = 0 k₃ = 0.0, k₁-k₂ plane: z₂ = 0 k₃ = 0.5, k₁-k₂ plane: z₂ = 1 So, for the k₃ direction, my results are exactly the opposite of those reported in the example. Here is my POSCAR file: Bi2Se3 1.0 -2.069 -3.583614 0.000000 2.069 -3.583614 0.000000 0.000 2.389075 9.546667 Bi Se 2 3 Direct 0.3990 0.3990 0.6970 0.6010 0.6010 0.3030 0 0 0.5 0.2060 0.2060 0.1180 0.7940 0.7940 0.8820 I'm unable to figure out why this discrepancy is occurring. I am using VASP.6.4.3, and my projection part is coming completely fine (perfect overlapping). Also, when I am using the provided wannier90_hr.dat file and calculated the Z₂ values, it is coming correct with VASP.6.4.3. I am new to these calculations, please suggest as I am not getting why this is happening. If my output files are required, plet let me know. _______________________________________________ Wannier mailing list [email protected] https://lists.quantum-espresso.org/mailman/listinfo/wannier
