Dissociation dynamics of high-v Rydberg states of molecular hydrogen

Journal Article · Thu Dec 31 23:00:00 EST 1992 · Journal of Chemical Physics

DOI:https://doi.org/10.1063/1.464495· OSTI ID:6585759

McCormack, E. F. ^[1]; Pratt, Stephen T. ^[1]; Dehmer, Patricia M. ^[1]; Dehmer, Joseph L. ^[1]

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1. Argonne National Lab. (ANL), Argonne, IL (United States)

A high-resolution, state-selective investigation of the decay of (X ²Σ⁺_g)np, v'≥9 Rydberg states of H₂ into the H(1s)+H(3I) and H(1s)+H(4I) dissociation continua has been performed. The (X ²Σ⁺_g)np Rydberg states were excited by double-resonance excitation via the E,F ¹Σ_g⁺, v=6, J=0 and 1 states, and the H(3I) and H(4I) dissociation products were detected by monitoring the energy-resolved photoelectrons produced by nonresonant photoionization of the fragments. The energy region of interest (138 800--140 000 cm⁻¹) includes the X ²Σ⁺_g, v⁺=9, N⁺=0--3 ionization thresholds, the H(1s)+H(4I) dissociation threshold, and the H⁺+H⁻ ion-pair threshold. Evidence of both direct and indirect dissociation involving both singly and doubly excited electronic states is observed. Comparisons to the previously observed X ²Σ⁺_g, v⁺=8 constant-ionic-state photoelectron spectrum and the ion-pair spectrum observed in the same energy region reveal strong competition between the ionization and dissociation processes through both rovibrational and electronic interactions.

• Research Organization: Argonne National Laboratory (ANL), Argonne, IL (United States)
• Sponsoring Organization: USDOE; Office of Energy Research (OER); Office of Health and Environmental Research (OHER)
• DOE Contract Number: W-31109-ENG-38
• OSTI ID: 6585759
• Journal Information: Journal of Chemical Physics, Journal Name: Journal of Chemical Physics Journal Issue: 11 Vol. 98; ISSN JCPSA6; ISSN 0021-9606
• Publisher: American Institute of Physics (AIP)
• Country of Publication: United States
• Language: English

Related Subjects

664200* -- Spectra of Atoms & Molecules & their Interactions with Photons-- (1992-)
74 ATOMIC AND MOLECULAR PHYSICS
DISSOCIATION
DOUBLE RESONANCE METHODS
ELEMENTS
EMISSION
ENERGY
ENERGY LEVELS
ENERGY-LEVEL TRANSITIONS
EXCITATION
EXCITED STATES
HYDROGEN
IONIZATION
NONMETALS
PHOTOEMISSION
PHOTOIONIZATION
RESOLUTION
RYDBERG STATES
SECONDARY EMISSION
THRESHOLD ENERGY
VIBRATIONAL STATES