title: Simultaneous Two-Photon Absorption to Gerade Excited Singlet States of Diphenylacetylene and Diphenylbutadiyne Using Optical-Probing Photoacoustic Spectroscopy.
abstract: Simultaneous two-photon absorption to one-photon forbidden electronically excited states of diphenylacetylene (DPA) and diphenylbutadiyne (DPB) was investigated by means of highly sensitive optical-probing photoacoustic spectroscopy. The incident laser power dependencies on photoacoustic signal intensity indicate that the signals are dominated by the two-photon absorption regime. Two-photon absorption is responsible for transitions to gerade excited states based on the selection rule. The two-photon absorption bands observed in the heat action spectra were assigned with the aid of quantum chemical calculations. The relative magnitude of the two-photon absorption cross sections of DPA and DPB was estimated, and the larger two-photon absorption cross section of DPB was related to the resonance effect with the red-shifted one-photon allowed 1(1)B1u ← 1(1)Ag transition of DPB.
authors.affiliation: Department of Chemistry and Biological Science, Aoyama Gakuin University , 5-10-1 Fuchinobe, Chuo-ku, Sagamihara, Kanagawa 252-5258, Japan.
authors.forename: Tasuku
authors.initials: T
authors.lastname: Isozaki
authors.affiliation: Department of Chemistry and Biological Science, Aoyama Gakuin University , 5-10-1 Fuchinobe, Chuo-ku, Sagamihara, Kanagawa 252-5258, Japan.
authors.forename: Hikari
authors.initials: H
authors.lastname: Oba
authors.affiliation: Graduate School of Science and Technology, Niigata University , 2-8050 Ikarashi, Nishi-ku, Niigata 950-2181, Japan.|CREST, Japan Science and Technology Agency , 4-1-8 Honcho, Kawaguchi 332-0012, Japan.|Center for Instrumental Analysis, Niigata University , 2-8050 Ikarashi, Nishi-ku, Niigata 950-2181, Japan.
authors.forename: Tadaaki
authors.initials: T
authors.lastname: Ikoma
authors.affiliation: Department of Chemistry and Biological Science, Aoyama Gakuin University , 5-10-1 Fuchinobe, Chuo-ku, Sagamihara, Kanagawa 252-5258, Japan.
authors.forename: Tadashi
authors.initials: T
authors.lastname: Suzuki