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I would like to ask how to use PHONOPY to define which band is LO, TO or LA, TA. I have read the answer: other matter modeling answer, it's very helpful. In this answer, @Xivi76 provides a way to see the eigenvectors of the modes and then compare to the 'q' shift of supercell. I'm confused how to see the 'q' shift, when creating a supercell, phonopy give us several supercell files, but each file only has one fixed shift.

Besides, I still meet some problems for my system, it's chemical disorder and I use a 32 atom supercell to calculate the phonon.

The mesh file I got is this:

frequency:    -0.0019387126
    eigenvector:
    - # atom 1
      - [  0.10015311494775,  0.00000000000000 ]
      - [  0.14574730400284,  0.00000000000000 ]
      - [  0.00001729724040,  0.00000000000000 ]
    - # atom 2
      - [  0.10013379473130,  0.00000000000000 ]
      - [  0.14580803218871,  0.00000000000000 ]
      - [  0.00000000032891,  0.00000000000000 ]
    - # atom 3
      - [  0.10015311494775,  0.00000000000000 ]
      - [  0.14574730400285,  0.00000000000000 ]
      - [ -0.00001729658241,  0.00000000000000 ]
    - # atom 4
      - [  0.10013946626706,  0.00000000000000 ]
      - [  0.14581888880191,  0.00000000000000 ]
      - [  0.00000000032896,  0.00000000000000 ]
    - # atom 5
      - [  0.10015738736556,  0.00000000000000 ]
      - [  0.14580019696621,  0.00000000000000 ]
      - [  0.00002316713376,  0.00000000000000 ]
    ……
    - # atom 32
      - [  0.09997189974928,  0.00000000000000 ]
      - [  0.14553902989387,  0.00000000000000 ]
      - [ -0.00002282659679,  0.00000000000000 ]

It seems the vibration mode is too complexity, how can I deal it?

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