Dynamics in singlet "excited" state

[StKolev]

Dear CP2K  users/developers

I am trying to simulate the process in which an electron absorbs
energy (from a photon) and detaches from a closed shell system
(anion), leaving radical. A:(-) + hv = A. + e- . To do this I just ran
the simulation in triplet state, forcing an electron from HOMO to
change spin and occupy LUMO orbital of the system. Is it possible to
force an electron from HOMO to occupy LUMO and not change spin, and
run dynamics with that system. With other words, is it possible to
have my system still in excited state but singlet and not triplet.

Thank you for your help.