Rotational autoionization of np Rydberg series of D₂

Journal Article · Sun Dec 31 23:00:00 EST 1989 · Journal of Chemical Physics

DOI:https://doi.org/10.1063/1.458473· OSTI ID:7103609

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)

Two-color resonantly enhanced multiphoton ionization combined with photoelectron spectroscopy was used to study rotational autoionization of np Rydberg states of D₂ near the first ionization threshold. This work represents an extension of the study by O'Halloran et al. [J. Chem. Phys. 90, 930 (1989)] on the analogous states of H₂. As in that work, one laser was used to excite a two-photon transition to the E, F ¹Σ⁺_g, v´=0, E0, J´=0--4 levels, and a second laser was used to probe single-photon transitions to the rotationally autoionized np Rydberg states converging to the X ²Σ⁺_g, v⁺=0, N⁺ =1--6 rotational levels of D⁺₂. Of the five dipole-allowed Rydberg series converging to v⁺=0 excited from each intermediate J´ level (J´≥2), two are allowed to rotationally autoionize in a coupling scheme that assumes ejection of pure p waves in the ionization process and singlet coupling of the spins of the ion core and the outgoing electron; members of these Rydberg series have large half-widths. As in H₂, autoionization requiring the change of four quanta of rotational energy was found to be significantly slower than that requiring the minimum change of two quanta. Ionization was also observed for the series that are forbidden to rotationally autoionize according to this simple coupling scheme, and it is shown that both the inclusion of f waves in the autoionization process and singlet--triplet mixing may be required to explain these observations. By extending the wavelength region of the J´=4 spectrum beyond that of the earlier study on H₂, rotational autoionization requiring even higher partial waves was observed.

• Research Organization: Argonne National Laboratory (ANL), Argonne, IL (United States)
• Sponsoring Organization: USDOE; Office of Health and Environmental Research (OHER)
• DOE Contract Number: W-31109-ENG-38
• OSTI ID: 7103609
• Journal Information: Journal of Chemical Physics, Journal Name: Journal of Chemical Physics Vol. 92:1; ISSN JCPSA; ISSN 0021-9606
• Publisher: American Institute of Physics (AIP)
• Country of Publication: United States
• Language: English

Related Subjects

640302* -- Atomic
Molecular & Chemical Physics-- Atomic & Molecular Properties & Theory
74 ATOMIC AND MOLECULAR PHYSICS
AUTOIONIZATION
DEUTERIUM
ELECTRON SPECTROSCOPY
ENERGY LEVELS
EXCITED STATES
HYDROGEN ISOTOPES
IONIZATION
ISOTOPES
LIGHT NUCLEI
MULTI-PHOTON PROCESSES
NUCLEI
ODD-ODD NUCLEI
PHOTOELECTRON SPECTROSCOPY
ROTATIONAL STATES
RYDBERG STATES
SPECTROSCOPY
STABLE ISOTOPES