[Pw_forum] ph.x can only address LDA potentials?

[刘永铎]

Dear Pw user:


     I am trying to calculate Raman spectrum of some stuff. But it seems that the ph.x complains whenever I use potentials other than LDA. It gives error messages like:
   
     The phonon code with ### and raman, elop or elph is not yet available.
 
     So, is the lda-potentail our only choice?   But the calculated Raman mode is very bad comparative to the experimental results. For instance, SiH4, it gives:

#  mode   [cm-1]     [THz]      IR           Raman     depol
    1      0.00    0.0000    0.0000         0.0791    0.7500
    2      0.00    0.0000    0.0000         0.1194    0.7500
    3      0.00    0.0000    0.0000         0.0679    0.7500
    4      0.00    0.0000    0.0000         0.0970    0.7500
    5      0.00    0.0000    0.0000         0.0051    0.7500
    6      0.00    0.0000    0.0000         0.0235    0.7500
    7    634.67   19.0268    1.0902         1.1145    0.7500
    8    634.67   19.0268    1.0902         1.1145    0.7500
    9    634.67   19.0268    1.0902         1.1145    0.7500
   10    819.69   24.5735    0.0000         8.4725    0.7500
   11    819.69   24.5735    0.0000         8.4725    0.7500
   12   2524.31   75.6765    0.0000       267.0683    0.0000    ? this one?
   13   2546.65   76.3462    3.3789        81.6301    0.7500
   14   2546.65   76.3462    3.3789        81.6301    0.7500
   15   2546.65   76.3462    3.3789        81.6301    0.7500


but the experimental value is 2187 cm-1


best


Yongduo

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