Ion-pair formation in the photodissociation of HF and DF
- Department of Chemistry and Department of Physics, State University of New York at Albany, Albany, New York 12222 (United States)
- EPSRC Daresbury Laboratory, Daresbury, Warrington WA4 4AD, England (United Kingdom)
- Department of Chemistry, Brookhaven National Laboratory, Upton, New York 11973 (United States)
- Laboratoire de Photophysique Moleculaire, Batiment 213, Universite de Paris-Sud, 91405 Orsay Cedex (France)
The excitation functions for ion-pair formation in supersonically cooled HF and DF have been measured using synchrotron radiation with photon resolutions of 0.12 and 0.06 nm. The excitation functions for both molecules are characterized by an intense, sharp peak, essentially coincident with the thermodynamic onset for ion-pair formation, followed by weaker, broader structure to higher energy. All of the structure is interpreted as arising from the photoexcitation of Rydberg states of the neutral molecules that are predissociated by the {ital V} {sup 1}{Sigma}{sup +} ion-pair state potential. {ital Ab} {ital initio} calculations using multichannel quantum defect theory to include both predissociation and autoionization enabled assignments of the observed structure to be made and the construction of simulated ion-pair excitation function spectra in an energy region encompassing {similar_to}0.25 eV of the lowest energy part of the experimental excitation functions. The intense first peak in the ion-pair excitation function of both molecules is assigned to a high vibrational level of the 3{ital s}{sigma} Rydberg state converging to the {ital A} {sup 2}{Sigma}{sup +} ion state, while most of the structure immediately following the first peak is assigned to {ital d} Rydberg complexes converging to the {ital v}{sup +}=1 level of both {ital X} {sup 2}{Pi} ion substates. {copyright} {ital 1995} {ital American} {ital Institute} {ital of} {ital Physics}.
- OSTI ID:
- 83912
- Journal Information:
- Journal of Chemical Physics, Journal Name: Journal of Chemical Physics Journal Issue: 8 Vol. 103; ISSN JCPSA6; ISSN 0021-9606
- Country of Publication:
- United States
- Language:
- English
Similar Records
High-resolution photoionization spectrum of water molecules in a supersonic beam
Dissociation and ionization of vibrationally autoionizing Rydberg states of H[sub 2] in a static electric field
Optical probes of atomic and molecular decay processes.
Journal Article
·
Sun Feb 14 19:00:00 EST 1988
· J. Chem. Phys.; (United States)
·
OSTI ID:5714759
Dissociation and ionization of vibrationally autoionizing Rydberg states of H[sub 2] in a static electric field
Journal Article
·
Sun Aug 15 00:00:00 EDT 1993
· Journal of Chemical Physics; (United States)
·
OSTI ID:5406941
Optical probes of atomic and molecular decay processes.
Conference
·
Fri Dec 31 23:00:00 EST 2004
·
OSTI ID:1007387