Two-photon absorption properties of star-shaped molecules containing peripheral diarylthienylamines

Two-photon absorption (TPA) properties of several novel donor-acceptor-donor (D-A-D) quadrupolar and octupolar star-shaped molecules containing peripheral diarylthienylamines were investigated and are discussed in this Letter. The effects of donor-acceptor strength, conjugation length, and molecular symmetry on the effective TPA cross-section of these novel molecules were studied. It was found that incorporation of a triazine acceptor center in octupolar molecules can effectively enhance TPA response. This provides a strategy for designing novel octupolar molecules with a large TPA response but without red-shifting their linear absorption wavelengths. (C) 2004 Published by Elsevier B.V.