CASTEP > CASTEP jobs > CASTEP file formats > phonon

CASTEP file formats - PHONON

The .phonon file contains phonon frequencies and eigenvectors for all q-vectors in a CASTEP phonon calculation. The data in this file are used for phonon dispersion plotting, phonon DOS, and projected (partial) phonon DOS calculations. Phonon frequencies are always given in wavenumbers (cm-1).

The file has the following format (the blocks with frequencies and eigenvectors are printed out for each of the wavevectors):

 BEGIN header
 Number of ions                    2
 Number of branches                6
 Number of wavevectors            10
 Unit cell vectors (ANG)
    0.000000    2.693725    2.693725
    2.693725    0.000000    2.693725
    2.693725    2.693725    0.000000
 Fractional Co-ordinates
     1     0.000000    0.000000    0.000000   Si    28.084999
     2     0.250000    1.250000    0.250000   Si    28.084999
 END header
     q-pt=    1    0.400000  0.400000  0.400000      0.064000
              1      109.544856                                        
              2      109.544856                                        
              3      339.376813                                        
              4      443.097011                                        
              5      489.759189                                        
              6      489.759189                                        
                        Phonon Eigenvectors
Mode Ion                X                                   Y                                   Z
   1   1 -0.165228427057 -0.116020562843     -0.284044331893 -0.233521205707      0.449272758949  0.349541768550
   1   2  0.201651690195 -0.009889385798      0.367580652434  0.009889385798     -0.569232342629  0.000000000000
   2   1 -0.388589746163 -0.376258074200      0.312443981299  0.317015387463      0.076145764864  0.059242686737
   2   2  0.537742986688  0.058349031619     -0.441265665838 -0.058349031619     -0.096477320851  0.000000000000
   3   1 -0.244303700263  0.327081593344     -0.244303700263  0.327081593344     -0.244303700263  0.327081593344
   3   2 -0.408248290464  0.000000000000     -0.408248290464  0.000000000000     -0.408248290464  0.000000000000
   4   1 -0.244303700263  0.327081593344     -0.244303700263  0.327081593344     -0.244303700263  0.327081593344
   4   2  0.408248290464  0.000000000000      0.408248290464  0.000000000000      0.408248290464  0.000000000000
   5   1  0.337915678624  0.446590624106     -0.201465712757 -0.340430253958     -0.136449965866 -0.106160370148
   5   2  0.540936209585  0.144976579344     -0.368052961771 -0.144976579344     -0.172883247814  0.000000000000
   6   1  0.132744701086  0.045628787713      0.302026038793  0.292630165905     -0.434770739880 -0.338258953618
   6   2  0.132788915152 -0.045499955467      0.418069248043  0.045499955467     -0.550858163195  0.000000000000
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See Also:

CASTEP jobs
CASTEP file formats

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