Near-infrared femtosecond laser ionization of the acetic acid dimer

Fragment ions produced after the ionization of the acetic acid dimer (CH3COOH)(2) in a near-infrared intense femtosecond laser field were measured using time-of-flight mass spectrometry. The two-body Coulomb explosion (CE) process (CH3COOH)(2)(2+) -> 2CH(3)COOH(+) with a kinetic energy release of 3.4 eV, similar to the case of (HCOOH)(2)(2+) (Hoshina et al., 2012), was identified. The two-body CE of (CH3COOH)(2)(2+) was induced when the laser polarization direction was perpendicular to the C center dot center dot center dot C intermolecular axisin contrast to the case of (HCOOH)(2)(2+). The preferential configurations may be those that deform dimer structures close to dimer dications during the double-ionization process. (C) 2015 Elsevier B.V. All rights reserved.