[CPMD-list] ROKS and TDDFT of spin polarized systems

[Eneritz Muguruza]

Hello everyone,

      Here I ask another question. I am studying the isomerization of a
chromophore of a photoreceptor protein. I am doing that by calculating
potential energy surfaces of the ground and first excited singlet state along
the isomerization coordinate, the torsional angle around a double bond. I am
calculating the excited states with ROKS and TDDFT. At the twisted angle of 90
degrees in the ground state the double bond breaks and a spin unrestricted
(LSD) calculation is necessary. My question is: how can I calculate the excited
state of that structure?

- I tried to do the calculation with TDDFT but only a mixed state was obtained.
Is there the spin-unrestricted TDDFT implemented on CPMD?

- ROKS is a spin restricted method, but could I somehow do different
calculatiosn by transfering the electron at HOMO with spin-up and spin-down and
then do a linear combination to get the right spin?

Thank you very much for any hints or comments.
  
        Regards,

              
             Eneritz


-- 
Eneritz Muguruza
eneritz.muguruza at kcl.ac.uk