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Title: Light-induced potentials ignite dissociation of N{sub 2}{sup 2+}

Abstract

Direct ionization to dissociative potential curves is the dominant explanation for intense-field dissociative ionization of N{sub 2}. In this article we contradict this notion by showing that the dissociation of N{sub 2}{sup 2+} adiabatically follows the avoided crossing formed by the vertical bar X {sup 3}{pi}{sub u},n> and vertical bar D {sup 3}{pi}{sub g},n-1> dressed curves. Dissociation along this light-induced molecular potential implies that one photon is absorbed and adds to the kinetic release of the fragments. We compare the fragmentation energies for three different laser wavelengths and find that nitrogen shows photon absorption whereas iodine does not. From this we conclude that one must account for the absorbed photon when interpreting the time-of-flight spectra for molecules with appreciable nuclear motion during the laser pulse. In nitrogen, doing so allows us to identify enhanced ionization of the dication at 2.2 A independent of laser wavelength.

Authors:
; ;  [1]
  1. University of Connecticut, Storrs, Connecticut 06269-3046 (United States)
Publication Date:
OSTI Identifier:
20787135
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. A; Journal Volume: 73; Journal Issue: 4; Other Information: DOI: 10.1103/PhysRevA.73.043417; (c) 2006 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
74 ATOMIC AND MOLECULAR PHYSICS; ABSORPTION; COMPARATIVE EVALUATIONS; DISSOCIATION; IODINE; IONIZATION; LASER RADIATION; MOLECULES; NITROGEN; PHOTONS; POTENTIALS; PULSES; RINGS; TIME-OF-FLIGHT METHOD; VISIBLE RADIATION; WAVELENGTHS

Citation Formats

Coffee, Ryan N., Fang Li, and Gibson, George N.. Light-induced potentials ignite dissociation of N{sub 2}{sup 2+}. United States: N. p., 2006. Web. doi:10.1103/PHYSREVA.73.0.
Coffee, Ryan N., Fang Li, & Gibson, George N.. Light-induced potentials ignite dissociation of N{sub 2}{sup 2+}. United States. doi:10.1103/PHYSREVA.73.0.
Coffee, Ryan N., Fang Li, and Gibson, George N.. Sat . "Light-induced potentials ignite dissociation of N{sub 2}{sup 2+}". United States. doi:10.1103/PHYSREVA.73.0.
@article{osti_20787135,
title = {Light-induced potentials ignite dissociation of N{sub 2}{sup 2+}},
author = {Coffee, Ryan N. and Fang Li and Gibson, George N.},
abstractNote = {Direct ionization to dissociative potential curves is the dominant explanation for intense-field dissociative ionization of N{sub 2}. In this article we contradict this notion by showing that the dissociation of N{sub 2}{sup 2+} adiabatically follows the avoided crossing formed by the vertical bar X {sup 3}{pi}{sub u},n> and vertical bar D {sup 3}{pi}{sub g},n-1> dressed curves. Dissociation along this light-induced molecular potential implies that one photon is absorbed and adds to the kinetic release of the fragments. We compare the fragmentation energies for three different laser wavelengths and find that nitrogen shows photon absorption whereas iodine does not. From this we conclude that one must account for the absorbed photon when interpreting the time-of-flight spectra for molecules with appreciable nuclear motion during the laser pulse. In nitrogen, doing so allows us to identify enhanced ionization of the dication at 2.2 A independent of laser wavelength.},
doi = {10.1103/PHYSREVA.73.0},
journal = {Physical Review. A},
number = 4,
volume = 73,
place = {United States},
year = {Sat Apr 15 00:00:00 EDT 2006},
month = {Sat Apr 15 00:00:00 EDT 2006}
}
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