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

Graham, P., Ledingham, K.W.D., Singhal, R.P., McCanny, T., Hankin, S.M., Fang, X., Tzallas, P., Kosmidis, C., Taday, P.F. and Langley, A.J. (2000) Angular distributions of fragment ions from labelled and unlabelled N₂O in intense laser fields. Journal of Physics B: Atomic, Molecular and Optical Physics, 33(18), 3779 -3794. (doi: 10.1088/0953-4075/33/18/325)

Abstract

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 (approx. 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 approx. 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.

• Item Type: Articles
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: UNSPECIFIED
• Authors: Graham, P., Ledingham, K.W.D., Singhal, R.P., McCanny, T., Hankin, S.M., Fang, X., Tzallas, P., Kosmidis, C., Taday, P.F., and Langley, A.J.
• Subjects: Q Science > QC Physics
• College/School: College of Science and Engineering > School of Physics and Astronomy
• Journal Name: Journal of Physics B: Atomic, Molecular and Optical Physics
• ISSN: 0953-4075