Second Derivative for DC-DFT

How To
#1

Hello,

I have a question if the calculation of second derivatives are available for DC-DFT calculations and also for MBD dispersion. I am trying to explore this analysis to get force constant but I got a bit lost on the manual and did not understand very much if it’s available or not.

Thanks in advance

#2

Analytic first derivatives for DC-DFT are available although I don’t think that the coupled-perturbed equations are parallelized. Analytic 2nd derivatives are not available but frequencies could be computed by finite-difference of gradients.