Takuichiro OMI (Grad. School Waseda Univ.), Hiroshi SHITOMI (Grad. School Waseda Univ.), Nobutake SEKIYA (Grad. School Waseda Univ.), Ken TAKAZAWA (National Research Institute for Metals) and Masaaki FUJII
[Chem. Phys. Lett. 252, 287 (1996)]
A spectroscopic technique for the measurement of the IR transition in a supersonic jet has been developed. This spectroscopy, the nonresonant ionization detected IR spectroscopy (NID-IR), detects the IR transition by the selective ionization of the vibrationally excited molecule. Because of the ionization detection, it has high sensitivity. Furthermore, the ionization detection allows us to observe the IR spectrum of a specific molecular species by selecting mass of the corresponding cation. The advantage of the NID-IR spectroscopy has been demonstrated by the observation of the IR spectra of phenol, o-fluorophenol, acetylene and 7-azaindole in a supersonic jet. The assignments of cis and trans rotational isomers in o-fluorophenol are also discussed.