Ionization-induced π → H site-switching in phenol-CH4 complexes studied using IR dip spectroscopy.
IR spectra of phenol-CH4 complexes generated in a supersonic expansion were measured before and after photoionization. The IR spectrum before ionization shows the free OH stretching vibration (ν(OH)) and the structure of neutral phenol-CH4 in the electronic ground state (S0) is assigned to a π-bound geometry, in which the CH4 ligand is located above the phenol ring. The IR spectrum after ionization to the cationic ground state (D0) exhibits a red shifted ν(OH) band assigned to a hydrogen-bonded cationic structure, in which the CH4 ligand binds to the phenolic OH group. In contrast to phenol-Ar/Kr, the observed ionization-induced π → H migration has unity yield for CH4. This difference is attributed to intracluster vibrational energy redistribution processes.
Chemical Resources Laboratory, Tokyo Institute of Technology, 4259 Nagatsuta, Yokohama, 226-8503, Japan. mfujii@res.titech.ac.jp.
Mitsuhiko
M
Miyazaki
Akihiro
A
Takeda
Matthias
M
Schmies
Makoto
M
Sakai
Kentaro
K
Misawa
Shun-ichi
S
Ishiuchi
François
F
Michels
Klaus
K
Müller-Dethlefs
Otto
O
Dopfer
Masaaki
M
Fujii
D006859:Hydrogen / Q000737:chemistry*; D006860:Hydrogen Bonding; D008697:Methane / Q000737:chemistry*; D008958:Models, Molecular; D008968:Molecular Conformation; D010636:Phenols / Q000737:chemistry*; D011789:Quantum Theory; D013055:Spectrophotometry, Infrared
D010636:Phenols; D006859:Hydrogen; D008697:Methane