Yoshiya Inokuchi

Formation of benzene dimer cations in neat liquid benzene studied by femtosecond transient absorption spectroscopy

Abstract Photoionization of neat liquid benzene has been studied by femtosecond pump-probe experiments in the near infrared region. A transient species is formed within 1 ps following two-photon excitation of liquid benzene at 268 nm, which shows a broad absorption band with a peak at 920 nm and extended intensities at wavelengths longer than 1000 nm. This band is attributed to a charge resonance band of a localized benzene dimer cation. The transient species show essentially no evidence of the recombination with electrons in a time shorter than 50 ps.

Pump - Probe photodepletion spectroscopy of (C6H6)+ 2. Identification of spectrum in the charge resonance band region

This work was supported in part by Grant-in-Aid for research programs (07740465 and 07454190) from the Ministry of Education, Science, Sports and Culture of Japan. K. O. received financial support from the Morino Science Foundation.

Infrared photodissociation spectroscopy of benzene trimer ions. Switching of the dimer ion core in vibrationally excited states

Abstract A vibrational spectrum of benzene trimer ion, (C 6 H 6 ) 3 + , was measured in the 2900–3100 cm −1 region by infrared photodissociation spectroscopy. An intense band at 2986 cm −1 was attributed to a Cue5f8H stretching vibration of the dimer ion core in (C 6 H 6 ) 3 + . The spectra of isotopically mixed benzene trimer ions with benzene- d 6 molecules were also obtained. From the analysis of asymmetric band shape, a switching of the dimer ion core is proposed to occur in the vibrationally excited state prior to the vibrational predissociation.

PHOTODISSOCIATION SPECTROSCOPY OF PHENOL DIMER ION. LACK OF RESONANCE INTERACTION BETWEEN THE AROMATIC RINGS

This is a postprint of an article published by Elsevier B.V. in Chemical Physics Letters, 1996, available online: http://doi.org/10.1016/0009-2614(96)00522-2

Photodissociation spectrum of cyanobenzene dimer cation. Absence of intermolecular resonance interaction

Electronic spectra of a homo-molecular dimer cation, (C6H5CN)2+, are measured by photodissociation spectroscopy in the gas phase. Broad features appeared in the 450–650 nm region are characteristic of π3 → πCN transitions of the C6H5CN+ chromophore. No intense band is observed in the 650–1300 nm region, where other aromatic dimer cations usually show charge resonance bands. Two component molecules of (C6H5CN)2+ cannot take a parallel sandwich configuration suitable for the resonance interaction, because of geometrical constraints due to other stronger interactions.