Chemical Physics Letters, Vol.362, No.3-4, 255-260, 2002
Observation of sharp vibronic bands in the O-4(-)'core ion' by mid infrared predissociation spectroscopy of O-4(-)center dot Ar-n clusters
We report the first observation of an infrared (v(0.0) similar to 4150 cm(-1)) electronic band system arising from excitation of the ground state O-4(-) ion, which we discuss in the context of the expected transition (J. Chem. Phys. 114 (2001) 3010) between the two low lying isomeric forms of this species. Surprisingly, the band displays sharp vibrational fine structure, opening the way for a detailed spectroscopic characterization of a charge-resonance stabilized dimer ion. (C) 2002 Elsevier Science B.V. All rights reserved.