title: Two-photon absorption properties of azulenyl compounds having a conjugated ketone backbone.
abstract: Two-photon absorption (TPA) properties of newly synthesized conjugated ketone derivatives that include nonalternant azulenyl moieties in the pi-conjugation system, alpha,alpha'-bis(1-azulenylidene)cyclopentanone (1Az), alpha,alpha'-bis(2-azulenylidene)cyclopentanone (2Az), and alpha,alpha'-bis(6-azulenylidene)cyclopentanone (6Az) are reported. TPA spectra of these azulenyl compounds were measured using the open-aperture Z-scan method with a femtosecond laser. The TPA cross section at the peak position (sigma(2)peak) of 1Az was found to be the largest among the three azulenyl compounds, which is almost 7 times larger than that of the alpha,alpha'-bis(1-naphthylidene)cyclopentanone (1Nph), an alternant isomer of 1Az with the same number of pi-electrons. The small detuning energies of the azulenyl compounds compared to those of 1Nph were responsible for the large TPA cross sections. We report that a compound having an azulenyl moiety can be a promising TPA material.
authors.affiliation: Department of Chemistry, Faculty of Science, Yamaguchi University, Yoshida, Yamaguchi 753-8512, Japan.
authors.forename: Shoichiro
authors.initials: S
authors.lastname: Hirakawa
authors.forename: Jun
authors.initials: J
authors.lastname: Kawamata
authors.forename: Yasutaka
authors.initials: Y
authors.lastname: Suzuki
authors.forename: Seiji
authors.initials: S
authors.lastname: Tani
authors.forename: Toshihiro
authors.initials: T
authors.lastname: Murafuji
authors.forename: Kazuo
authors.initials: K
authors.lastname: Kasatani
authors.forename: Liudmil
authors.initials: L
authors.lastname: Antonov
authors.forename: Kenji
authors.initials: K
authors.lastname: Kamada
authors.forename: Koji
authors.initials: K
authors.lastname: Ohta
mesh_terms: D000042:Absorption; D052176:Azulenes / Q000737:chemistry*; D003517:Cyclopentanes / Q000737:chemistry; D007659:Ketones / Q000737:chemistry*; D017785:Photons
chemical_list: D052176:Azulenes; D003517:Cyclopentanes; D007659:Ketones; C007201:cyclopentanone