Photoelectron branching ratios and asymmetry parameters for the two outermost molecular orbitals of hydrogen cyanide

Journal Article · Fri Apr 13 23:00:00 EST 1984 · Journal of Physics. B, Atomic and Molecular Physics

DOI:https://doi.org/10.1088/0022-3700/17/7/018· OSTI ID:1169719

Holland, D. M. ^[1]; Parr, Albert C. ^[2]; Dehmer, Joseph L. ^[3]

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1. Univ. of Maryland, College Park, MD (United States). Inst. of Physical Science and Technology
2. National Bureau of Standards, Washington, DC (USA). Synchrotron Ultraviolet Radiation Facility
3. Argonne National Lab., IL (United States)

Triply differential photoelectron spectroscopy has been performed on hydrogen cyanide in the photon energy range 14.5 to 24 eV, using synchrotron radiation. Photoelectron branching ratios and asymmetry parameters are presented for the two outermost molecular orbitals. The vibrationally resolved branching ratio X² π (v₃=1)/(v₃=0) exhibits strong non-Franck-Condon behaviour from threshold to approximately 19 eV. The results are discussed in relation to similar studies on the isoelectronic molecules, N₂, CO and C₂H₂. The evidence suggests that the prominent non-Franck-Condon feature observed in the HCN⁺ X² π channel may arise, at least in part, from a shape resonantly enhanced autoionising state converging to a higher ionisation potential.

• Research Organization: Argonne National Laboratory (ANL), Argonne, IL (United States)
• Sponsoring Organization: USDOE
• DOE Contract Number: W-31109-ENG-38
• OSTI ID: 1169719
• Journal Information: Journal of Physics. B, Atomic and Molecular Physics, Journal Name: Journal of Physics. B, Atomic and Molecular Physics Journal Issue: 7 Vol. 17; ISSN 0022-3700
• Publisher: IOP Publishing
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
74 ATOMIC AND MOLECULAR PHYSICS