Dear Daniele,

1) I have seen in your paper : " Ab initio geometry and bright excitation of carotenoids: Quantum Monte Carlo and Many Body Green’s Function Theory calculations on peridinin"

that you assign symmetries to the excited states, namely Bu plus and Ag minus like symmetries.

I would like to know how you get these symmetries for the excited states because neither QE nor Abinit gives the symmetries of the orbitals participating in those specific transitions !?

I know that the excited state symmetry is a multiplication of symmetries of in that transition participating orbitals, but i have no idea how to extract the symmetries of the participating orbitals it self since QE and Abinit give both no information about participating orbital symmetries ? So how is it been done here in this paper ?

2) Assuming one has the excited state geometry of a single isolated molecule the calculation of its emission spectrum is the same as absorption spectrum calculation ?

(because i do not see any keyword specifying emission spectra calculations.)

If yes, it means i have to put this excited state geometry to abinit as it were the ground state to get KSS file and calculate in yambo absorption spectrum which in reality is a emission spectrum ? Is it correct how i am thinking ?

If no, how can i generally calculate emission spectra within yambo ?

3) As much as i looked in the tutorials and forum it seems that BSE calculations are unfortunately totally static,

so will there be in the next release a fully frequency dependent BSE as it is described in this paper : Double excitations in correlated systems: A many–body approach ?

Best Regards

Martin