  Circular dichroism (CD) spectroscopy is a useful technique for characterizing
chiral molecules. It is more sensitive than total absorption to molecule
conformation, and it is routinely used to identify enantiomers. We present here
absorption and CD spectra within the Time Dependent (TD) B3LYP approximation in
c-GlyPhe, a cyclo-dipeptide containing an aromatic group. Results from codes in
localized basis-set (Orca and MolGW) are carefully compared with the novel
TD-B3LYP implementation we developed in the Yambo code, that uses a plane-wave
basis set.
