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Results of analysis for the long-range interaction between ground state helium and triplet metastable helium, which shows that the long-range coefficient is the same for both gerade and ungerade states. Those terms which lead to the second term on the right hand side of a developed equation vanish through spin selection rules.
Long range interaction of two H atoms calculated with electrostatic Hellmann-Feynman theorem, determining part of second order molecular wave function
Deriving electron configurations and valence bond interaction energies for 18 molecular combinations of two ground-state oxygen atoms
Long range retarded interaction energies, obtaining energy term coefficient from minimal principle using Karplus and Kolker method
Long range atomic interaction potentials for nitrogen
Long-range electrostatic and electromagnetic interactions between two neutral hydrogenic atoms in ground state
Radial distribution function change due to small long-range interaction imposition on short range potential
Long range first order interaction between two excited hydrogen atoms yielding perturbation energy matrix, discussing diagonalization process
Low energy electron /or positron/ scattering by spherically symmetric atoms, discussing long range interactions
The subject of this dissertation is the numerical integration of the initial-value problem for the non-linear Vlasov equation. The Vlasov equation is used to describe the dynamics of a "collisionless", one-dimensional, classical electron gas confined between two perfectly reflecting boundaries. Only the long-range Coulomb interactions of the electrons are considered; effects associated with the discrete structure are neglected. The numerical results obtained for non-linear Landau damping compare well with similar results obtained by Knorr. A general statement of the results on stable initial conditions is: As the degree of non-linearity of the initial conditions is increased, the deviation from linear Landau damping appears sooner and is more severe. In some cases damping was observed to cease. Curves showing the time dependence of the damping decrement are derived and compared with predictions of non-linear theories. New results obtained in this study include the observation that for strongly non-linear cases, the damping of the electric field causes an initially Maxwellian fo (v, O) to develop a peak in the neighborhood of the phase velocity; strong growth of the second harmonic is seen after fo (v, t) develops such a peak. Also new in this study is the interpretation of the development of a certain class of strongly unstable initial conditions as approaching an inhomogeneous equilibrium.
Quadrupole-quadrupole interaction constant for Se and halogen diatomic molecules, discussing long range interatomic forces determination
Moderately long-range relativistic intermolecular forces, obtaining interaction energies
Retarded intermolecular forces, discussing Casimir and Polder retarded dipole-dipole energy of interaction between two ground state atoms in terms of trigonometric integrals
Long-range behavior of effective one-body potential representing particle compound system interaction, using modified effective range theory to extrapolate cross section data to zero energy
Accurate close coupling scattering calculations are presented for thermal energy HCl-He collisions. The interaction potential is obtained from the Gordon-Kim electron gas model, adjusted to have the correct long-range multipole form. A variety of phenomenological cross sections are computed from the close coupling S matrix, and these are compared with results from several commonly employed approximate methods. In particular, it is found that the total integral, total differential, and gas kinetic cross sections are accurately predicted by the central field approximation which retains just the spherical average of the interaction. Integral inelastic cross sections are represented quite accurately by the coupled states approximation of McGuire and Kouri, but only qualitatively by the effective potential method of Rabitz.
The use of the electrostatic Hellmann-Feynman theorem for the calculation of the leading term in the 1/R expansion of the force of interaction between two well-separated hydrogen atoms is discussed. Previous work has suggested that whereas this term is determined wholly by the first-order wavefunction when calculated by perturbation theory, the use of the Hellmann-Feynman theorem apparently requires the wavefunction through second order. It is shown how the two results may be reconciled and that the Hellmann-Feynman theorem may be reformulated in such a way that only the first-order wavefunction is required.
Atomic hydrogen 2s and 2p excitations by proton and He ion impact, considering ion-multipole interactions effect
The basic objectives of the study were to subject a set of runway configurations to cost analysis and to develop a dynamic programming model which would enable an airport to economically match the ground capacity to its air traffic demand. Quantitative differences in the capacity of runway configurations result from the various aircraft/aircraft and aircraft/air-system interactions. A problem formulation and solution procedure is presented which is intended to be a meaningful technique for the long-range planning of runway expansion programs.