Excess polarizabilities upon excitation from the ground state to the first dipole-allowed excited state of diphenylpolyenes

This paper discusses the excess polarizabilities upon excitation from the ground state to the first dipole-allowed excited state (S₁) of diphenylpolyenes by using the time-dependent density functional theory. Two hybrid exchange-correlation (xc) potentials Becke-3 Lee-Yang-Parr (B3LYP) and Perdew-Burke-Ernzerhof (PBE1PBE) were employed. Our calculations indicate that the magnitude of the excess polarizability will decrease while the molecule evolves from the unrelaxed S₁ state to the relaxed S₁ state. This decreasing trend is found to be independent of substituents, though substituents can change the value of the excess polarizability.