Abstract

POVEDA, J.C.; ALVAREZ, I.; GUERRERO-TAPIA, A.  and  CISNEROS, C.. Dissociation-ionization and ionization-dissociation by multiphoton absorption of acetaldehyde at 266 and 355 nm. Dissociation pathways. Rev. mex. fis. [online]. 2016, vol.62, n.3, pp.206-212. ISSN 0035-001X.

The experimental results from the interaction of a sample of acetaldehyde (CH3CHO) with laser radiation at intensities between 109 and 1011Wcm2 and wavelengths of 266 and 355 nm are reported. As a result of multiple photon absorption, cations from ionization-dissociation (I-D) or dissociation-ionization (D-I) processes, were detected using a reflectron time of flight mass spectrometer. The processes I-D is predominant at 355 nm and D-I is predominant at 266 nm. The formation of different ions is discussed. From analysis of the ratios between the ion currents [I( ${\mathrm{C}\mathrm{H}}_3\mathrm{}{\mathrm{C}\mathrm{O}}^{+}$)+I( ${\mathrm{C}\mathrm{O}}^{+}$)]/[ I( ${\mathrm{C}\mathrm{H}}_3^{+}$)+I( ${\mathrm{H}\mathrm{C}\mathrm{O}}^{+}$)], originated from the C-C bond or from the C-H bond breaking at different laser intensities, the predominant channels are determined.

Keywords : Acetaldehyde; photoionization; photodissociation; multiphoton processes; molecular dissociation.

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