The angular distributions of fragment ions from labelled and unlabelled N2O in intense laser fields

Autor: X. Fang, P. Graham, Kenneth W. D. Ledingham, Philip F. Taday, Paraskevas Tzallas, Constantine Kosmidis, A. J. Langley, Ravi P. Singhal, S. M. Hankin, T. McCanny
Rok vydání: 2000
Předmět:
Zdroj: Journal of Physics B: Atomic, Molecular and Optical Physics. 33:3779-3794
ISSN: 1361-6455
0953-4075
Popis: The mass spectra and angular distributions of fragment ions arising from a Coulomb explosion of highly charged parent nitrous oxide ions, obtained in the femtosecond regime (~1016 W cm-2), are investigated. The N ion angular distributions from 14N2O show maxima when the laser polarization is parallel and orthogonal to the time-of-flight axis. Measurements with labelled molecules (15N-14N = 16O) indicate that the maxima arise from the peripheral and central N atoms in the molecular structure. The anisotropic distributions may be explained by assuming increased ionization and fragmentation when the molecular axis is parallel to the laser field. The bond angle prior to explosion is determined to be ~140°, irrespective of the charge state of the precursor, and calculations of the kinetic energies imparted to the fragment ions suggest that dissociation occurs at the equilibrium internuclear distance of the neutral molecule.
Databáze: OpenAIRE