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​Dear Dr. QuanSheng and all users, Hope you are well. I was interested to study the topological properties of Chern insulator in 3D structures. Using the Wannier90 and then Wanniertools, I tried to calculate the Chern number of the compounds. I should mention that the band structure calculations with these codes produced expected results of DFT. According to the Wt.in and Wt.out attachment files, Chern numbers for 2 planes (k1=0 and k3=0) are nonzero. Does this mean that the structure under study is a Chern insulator? I request that you, if possible, please check whether the input files are correct or not. Any suggestions are welcome. Please find the attached files. I would appreciate your prompt response. Sincerely yours, Ali Dehghan, Shiraz university, Iran.

Dear Dr. QuanSheng and all users, Hope you are well. I was interested to study the topological properties of a compound in 3D half-Heusler structure. To start, I performed an accurate DFT calculation (with Quantum-Espresso) and extracted the spin-polarized band structure according to the band.pdf attachment file. This figure reveals that one of two spin channel (majority-channel) has two important characteristics: 1) the Dirac behavior in Gamma point and 2) the band inversion of d- and p-orbitals in the ascending order of energy (first the d-states and then the p-states are occupied). As you probably know, these two indications are necessary for a topological (or Chern) insulator. In the following, using the Wannier90 and then Wanniertools, I tried to calculate the Chern number of the compound. I should mention that the band structure calculations with these codes produced expected results. Contrary to my expectation, the chern number became zero. That's why I doubted my calculations. I request that you, if possible, please check whether the input files are correct or not. Any suggestions are welcome. Please find the attached files. I would appreciate your prompt response. Sincerely yours, Ali Dehghan, Shiraz university, Iran.

Dear QuanSheng, Thanks for prompt reply. Please find the attached files and let me know your useful comments. Best wishes, Ali