Molecular treatment of electron capture at low to intermediate collision energies: Collisions of B[sup 4+] ions with H atoms

Journal Article · Sat May 01 04:00:00 EDT 1993 · Physical Review A; (United States)

DOI:https://doi.org/10.1103/PhysRevA.47.3930· OSTI ID:6609595

Shimakura, N ^[1]; Suzuki, S ^[2]; Kimura, M ^[3]

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1. General Education Department, Niigata University, Niigata 950-21 (Japan)
2. Department of Chemistry, Faculty of Science, Niigata University, Niigata 950-21 (Japan)
3. Argonne National Laboratory, Argonne, Illinois 60439 (United States) Department of Physics, Rice University, Houston, Texas 77251 (United States)

Partial and total cross sections for electron capture in collisions of B[sup 4+] ions with H atoms from 100 meV/amu to 10 keV/amu have been rigorously determined by using the molecular-orbital expansion method modified by the inclusion of electron translation factors. Quantum-mechanical (3 channels) and semiclassical (12 channels) methods have been employed at collision energies lower than 30 eV/amu and higher than 15 eV/amu, respectively. The agreement of the present results with measurements above 1 keV/amu is reasonable. In our cross sections for the singlet manifold, rather large oscillatory structures are found below 10 eV/amu that are attributable to Stueckelberg-type oscillation. At collision energies below a few eV/amu, the B[sup 3+](1[ital s]3[ital d]) and B[sup 3+](1[ital s]3[ital p]) states are the dominant states for the triplet and singlet manifolds, respectively. However, the B[sup 3+](1[ital s]3[ital p]) state for the triplet and B[sup 3+](1[ital s]3[ital d]) state for the singlet take over above these energies. At energies above 1 keV/amu, three states, the B[sup 3+](1[ital s]3[ital s]), B[sup 3+](1[ital s]3[ital p]), and B[sup 3+](1[ital s]3[ital d]) states, contribute equally to the electron-capture process. A comparison of the present B[sup 4+] results with previous results for different projectiles with the same charge (i.e., Be[sup 4+], C[sup 4+], and N[sup 4+]) reveals that although the cross sections of all these systems lie roughly within a certain range of magnitudes at intermediate collision energies ([ital E]=0.5--10 keV/amu), differences begin to emerge in magnitude and energy dependence below this energy. We examined the scalability of the cross section; some remarks on the scaling are given.

• DOE Contract Number: W-31109-ENG-38
• OSTI ID: 6609595
• Journal Information: Physical Review A; (United States), Journal Name: Physical Review A; (United States) Vol. 47:5; ISSN 1050-2947; ISSN PLRAAN
• Country of Publication: United States
• Language: English

Related Subjects

664300* -- Atomic & Molecular Physics-- Collision Phenomena-- (1992-)
74 ATOMIC AND MOLECULAR PHYSICS
ATOM COLLISIONS
BORON IONS
CALCULATION METHODS
CAPTURE
CHARGED PARTICLES
COLLISIONS
CROSS SECTIONS
ELECTRON CAPTURE
ELEMENTS
ENERGY RANGE
EV RANGE
HYDROGEN
ION COLLISIONS
ION-ATOM COLLISIONS
IONS
KEV RANGE
MOLECULAR ORBITAL METHOD
MULTICHARGED IONS
NONMETALS
SCALING