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Infrared absorption and Raman spectroscopy in Phonon Software ver. 6.15

Phonon ver.6.15 calculates the spectra of one-phonon infrared absorption and non-resonant one-phonon Raman spectra from ab initio data. The spectra for different geometries of the crystal with respect to the beam can be shown as plots. Phonon provides the irreducible representations of phonons and determines the TO and LO group theoretical characters of the modes. The input data required by Phonon are the Born effective charge tensors and the Raman tensors. The lasts quantities are the derivative of the polarizibilities with respect to small atomic displacements. These quantities determine, respectively, the infrared absorption intensities, and Raman scattering intensities. Even if the ab initio data do not obey exactly the symmetry required by the tensors, Phonon reconstructs their correct symetries.
Below, some examples of infrared absorption and Raman spectra using VASP 5.2.2 and Phonon 6.15 are shown.
Phonon 6.15 provides five small programs (Fortran source and executables for Linux 32, 64 and Windows) which permit to prepare input data for calculating Hellmann-Feynman forces, effective charges, and Raman tensors by VASP, and obtain HFfile, Charge and Raman files for Phonon.



Last update: July 20, 2014