The electronic structure of energetically low-lying excited singlet states of fluorobenzene
molecules is investigated here. Increasing fluorine substitution alters the nature of the
excited electronic states and the so-called perfluoro effect is observed for penta-and
hexafluorobenzene. Detailed quantum chemistry calculations are carried out at the equation-
of-motion coupled-cluster singles and doubles level of theory to establish the potential
energy surfaces of the low-lying electronic states of mono-, di-(ortho-and meta-), and …