[QE-users] IR calculation for oriented single crystal

[Zack Gainsforth]

Hi All,

I have set up a calculation using pw.x -> ph.x -> dynmat.x successfully and plotted myself an IR spectrum.  The match to the experimental spectrum is good.  However, this is an IR spectrum assuming a powder where the photons are exciting all the modes.  I’d now like to calculate the spectrum for a single crystal and specify the electric vector of the photon relative to the crystal.  It should preferentially excite certain modes.

Is there a straightforward way to do this using ph.x + dynmat.x?  Or perhaps a way to read/print the dipole vectors for each mode so I can dot it with my photon’s e-field?  Or another way of thinking about this which is more efficient?  (Maybe I missed something in the documentation!)

Thanks,

Zack