[Pw_forum] Problem with Raman and Infrared Active Modes

[HASAN SAHIN]

>* According to this, my system has a symmetry.
*
it has no inversion symmetry. If I remember correctly, in systems
having inversion symmetry, modes are either IR- or Raman-active
but not both. Do you have any evidence that some of the modes
indicated as active are not?


There is no any experimental data on this structure, however I know some
structures (having C_3v symmetry) with seperated R and IR peaks.

Actually, being  R (or IR) active of acoustic modes arouses suspicion about
calculation.




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*SINCERELY

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  Hasan Sahin
  Bilkent University
  National Nanotechnology Research Center

  http://www.bilkent.edu.tr/~shasan/

  http://www.researcherid.com/rid/G-4747-2010

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