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Calculation of Raman Spectra
Vibrational Raman scattering cross sections are computed in the approximation
of the polarizability theory from derivatives of the frequencydependent
polarizability tensor with respect to normal modes of vibration,
= k_{ω}c_{i}α'^{2}(ω) + c_{a}γ'^{2}(ω) . 

Here,
α'^{2}(ω) and
γ'^{2}(ω) denote the isotropic part and
the anisotropy of the differentiated polarizability tensor, respectively. The
coefficients c_{i} and c_{a} depend on the scattering geometry and the
polarization of the incident and scattered radiation.
The factor
k_{ω} = 

includes the frequency ω_{v} and the degeneracy g_{v} of the vibration.
c is speed of light and
ε_{0} stands for the dielectric constant of
vacuum.
Computation of Raman spectra with TURBOMOLE is a threestep procedure.
First, vibrational frequencies and normal modes are calculated by aoforce.
Cartesian polarizability derivatives are computed in the second step by
egrad, see Section 7.4.7. Finally, the program
intense is used to project the polarizability derivatives onto vibrational
normal modes and to compute Raman scattering cross sections which are written
out along with vibrational frequencies and normal modes. The script
Raman can be used to perform all these steps automatically.
Next: Vibrational frequencies with fixed
Up: Calculation of Vibrational Frequencies
Previous: Analysis of Normal Modes
Contents
Index
TURBOMOLE