Title: The second-order stark effect on the 1B2u electronic origin of tetracene and pentacene in p-terphenyl
Abstract: The electric field induced shift of the electronic origin of the lowest B2u singlet state of tetracene and pentacene in p-terphenyl at 1.8°K has been measured. From this shift we calculate the difference in polarizability of this state and the ground state along the long molecular axis to be 4.5 ± 0.5 Å3 for tetracene and 19.8 ± 1.0 Å3 for pentacene (Fc′ = 0.505 Feff). The ratio of these tensor elements (Δα)zz for pentacene and tetracene is found to be 4.4 ± 0.6 and is independent of the local field approximation.