Infrared spectroscopy of size-selected neutral clusters combined with vacuum-ultraviolet-photoionization mass spectrometry

Intermolecular proton-transfer in acetic acid clusters induced by vacuum-ultraviolet photoionization

“…Details of the experimental setup for these spectroscopies were described elsewhere. 29,31 Briefly, in both the spectroscopic schemes, the size-selected cluster cation signal produced by VUV one-photon ionization of the neutral cluster is monitored with the Wiley-McLaren-type timeof-flight ͑TOF͒ mass spectrometer. In VUV-ID-IRPDS, the cluster cation signal is a measure of the population of the cluster under investigation.…”

“…26 Recently, several new vibrational spectroscopic techniques based on the VUV one-photon ionization detection have been developed and they enable us to apply IR spectroscopy to unstable cations such as the unprotonated cluster cations of the protic molecules. [27][28][29][30][31] We observed the infrared ͑IR͒ spectra of the unprotonated cluster cations of ammonia and methanol as the first examples of those of protic molecules. 29,[31][32][33][34] The structures of the unprotonated cluster cations were determined to be the proton-transferred type, where the dimer cation core of the protonated cation and counter radical are formed.…”

“…[27][28][29][30][31] We observed the infrared ͑IR͒ spectra of the unprotonated cluster cations of ammonia and methanol as the first examples of those of protic molecules. 29,[31][32][33][34] The structures of the unprotonated cluster cations were determined to be the proton-transferred type, where the dimer cation core of the protonated cation and counter radical are formed. 32,33 The theoretical calculations of the proton-transfer potentials and atomic charges indicated that the proton-transferred structures originate from intracluster proton-transfer reactions induced by the VUV onephoton ionization.…”

Observation of an Isolated Intermediate of the Nucleophilic Aromatic Substition Reaction by Infrared Spectroscopy

“…The experimental apparatus has been described elsewhere, [17,18] and only a brief description is given here. Resonance-enhanced multiphoton ionization is very inefficient for C 6 F 6 because of its fast internal conversion in its excited states.…”

A two-color tunable infrared/vacuum ultraviolet spectrometer for high-resolution spectroscopy of molecules in molecular beams

“…Coupled with an additional tunable IR laser, VUV photoionization becomes a versatile spectroscopists tool and indeed some recent publications (e.g., Refs. [6][7][8][9] begin to illustrate the potential of this technique. We describe here the development of a IR/VUV spectrometer system in our laboratory with an emphasis on the new methods employed to separate the generated VUV radiation from the a) Present address: University of Tokyo, 3-8-1 Komaba, Meguro, Tokyo 153-8902, Japan.…”