Results 251 to 260 of about 1,126,427 (279)

Negative Helium Ions

Physical Review, 1958
Negative helium ions have been produced with an ion source previously used for negative hydrogen ion production. Positive helium ions pass through a charge-exchange tube filled with hydrogen gas and the resulting negative ions are magnetically analyzed.
P. M. Windham, P. J. Joseph, J. A. Weinman   +2 more
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Negative Atomic Ions

The Journal of Chemical Physics, 1959
A semiempirical method is proposed for the computation of the electron affinities of negative atomic ions by extrapolation from the ionization potentials of the corresponding isoelectronic sequences. The method is based on a formula which can be justified on physical grounds and of which at least two parameters have direct physical interpretation.
H. R. Johnson, F. Rohrlich
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Negative-Ion Implantation

MRS Proceedings, 1994
AbstractNegative-ion implantation is a promising technique for forthcoming ULSI (more than 256 M bits) fabrication and TFT (for color LCD) fabrication, since the surface charging voltage of insulated electrodes or insulators implanted by negative ions is found to saturate within so few as several volts, no breakdown of insulators would be expected ...
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Modeling Multicusp Negative-Ion Sources

IEEE Transactions on Plasma Science, 2007
The study of negative-ion production and its optimization is of fundamental importance in the thermonuclear research field. Indeed, negative-ion beams are favorites for the generation of neutral particle beams used in fusion plasma heating because of their higher neutralization efficiency with respect to positive ions.
D Pagano, C Gorse, M Capitelli
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Photodetachment of negative halogen ions

Physical Review A, 1987
Results of relativistic random-phase approximation calculations of photodetachment cross sections and angular-distribution asymmetry parameters are presented for the outer shells of the negative ions ${\mathrm{F}}^{\mathrm{\ensuremath{-}}}$, ${\mathrm{Cl}}^{\mathrm{\ensuremath{-}}}$, ${\mathrm{Br}}^{\mathrm{\ensuremath{-}}}$, and ${\mathrm{I}}^{\mathrm{
, Radojevic, , Kelly, , Johnson
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Excited Negative Ions and Molecules and Negative Ion Production

1992
Abstract : Research has been performed to determine fundamental properties of negative ions; decay mechanisms and products of molecular Rydberg states; and mechanisms affecting H- production in ion source discharges. Experiments were performed on both stable and metastable states of Ca-, Cs-, He 2-, and WO3-; on the dissociative decay of Rydberg states
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Gas-phase solvated negative ions

Mass Spectrometry Reviews, 1998
The association of negative ions to neutral molecules has been an active field of research in gas-phase ion chemistry since 1970. For anions, which correspond to the conjugate base of well-known acids in solution, these species are often referred to as gas-phase solvated anions.
Keiko Takashima, José M. Riveros
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Regularities of Negative Ion Resonances

Topical Meeting on Multiple Excitations of Atoms, 1986
The effects of electron correlation in atomic and molecular systems are perhaps most pronounced in negative ions. No long-range Coulomb field is present to bind an additional electron to a parent state of a neutral atom. The stability of a negative ion state is thus usually attributed to one of two alternative mechanisms, both of which invoke electron ...
Charles W. Clark, Stephen J. Buckman
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Negative-Ion States

1985
Negative ions play important roles in many areas of photophysics and photochemistry. Negative ions can be produced directly by photodissociation of molecules through ion-pair production, or indirectly via charge exchange between photoexcited species and electronegative atoms or molecules.
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Atomic negative ions

AIP Conference Proceedings, 1992
We review some of the recent progress in the studies of alkaline‐earth, negative ions. Computations of autodetachment rates, electron affinities and transition wavelengths are discussed and some new and improved results are given.
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