Raman Intensity?

[attlbende]

Dear Developers,

Is it possible to compute Raman intensities together with the Frequency analysis using the GFN-xTB2 method?

Many thanks
Attila

[awvwgk]

Computing Raman intensities requires access to the polarizability tensor during the finite difference calculation of the hessian, which is currently not available since it is a response property. A surrogate could be the D4 isotropic polarizibility, however this is expected to provide insufficient accuracy. Even with the polarizability tensor of GFN2-xTB the resulting Raman intensities are expected to be poor as only a rather small basis set is used for all xTB Hamiltonians.