Tuning of quadratic nonlinear optical activity of chromophores with indolizine donor moiety and polyene π-bridge on the basis of electrochemical data

•Redox potentials of indolizine-based polyene chromophores are sensitive to acceptor nature.•For indolizine chromophore with octatetraene bridge β ∼1007⋅10−30 esu is predicted at ΔEel = 0.91 eV.•Almost linear correlation between β and 1/(ΔEel)2 is observed.•Composition analysis for frontier orbitals of studied chromophores is performed.