Near-threshold photodetachment of the Li sup minus ion

Journal Article · Fri Jan 31 23:00:00 EST 1992 · Physical Review A. General Physics; (United States)

DOI:https://doi.org/10.1103/PhysRevA.45.1544· OSTI ID:7205838

Dellwo, J; Liu, Y; Pegg, D J ^[1]; Alton, G D ^[2]

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1. Department of Physics, University of Tennessee, Knoxville, Tennessee 37996 (United States)
2. Physics Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States)

The method of threshold-photodetachment spectroscopy has been used to measure the electron affinity of Li. Changes in the partial cross sections for the resolved {ital h}{nu}+Li{sup {minus}}(2 {sup 1}{ital S}){r arrow}Li(2 {sup 2}{ital S})+{ital e}{sup {minus}}({epsilon}{ital p}) ({sup 2}{ital S}{epsilon}{ital p}) and {ital h}{nu}+Li{sup {minus}}(2 {sup 1}{ital S}){r arrow}Li(2 {sup 2}{ital P})+{ital e}{sup {minus}}({epsilon}{ital s}) ({sup 2}{ital P}{epsilon}{ital s}) channels were separately investigated in the vicinity of the 2 {sup 2}{ital P} threshold. The near-threshold data in the {sup 2}{ital P}{epsilon}{ital s} channel were fitted to a Wigner law to determine a threshold photon energy of 19 884.8{plus minus}1.6 cm{sup {minus}1}. An electron affinity of 4980.9{plus minus}1.6 cm{sup {minus}1} (617.6{plus minus}0.2 meV) is obtained upon subtraction of the well-known 2 {sup 2}{ital P} excitation energy. The position of the Wigner cusp in the {sup 2}{ital S}{epsilon}{ital p} channel was measured to be 19 882.4{plus minus}4.0 cm{sup {minus}1}, in agreement with the more precise {sup 2}{ital P}{epsilon}{ital s}-channel threshold energy.

• DOE Contract Number: AC05-84OR21400
• OSTI ID: 7205838
• Journal Information: Physical Review A. General Physics; (United States), Journal Name: Physical Review A. General Physics; (United States) Vol. 45:3; ISSN 1050-2947; ISSN PLRAA
• Country of Publication: United States
• Language: English

Related Subjects

664300* -- Atomic & Molecular Physics-- Collision Phenomena-- (1992-)
74 ATOMIC AND MOLECULAR PHYSICS
AFFINITY
ALKALI METALS
ANIONS
BEAMS
CHARGED PARTICLES
CROSS SECTIONS
ELEMENTS
ENERGY
ENERGY-LEVEL TRANSITIONS
EXCITATION
ION BEAMS
IONIZATION
IONS
LASER SPECTROSCOPY
LITHIUM
METALS
PHOTOIONIZATION
SPECTROSCOPY
THRESHOLD ENERGY