title: Atomic bound state and scattering properties of effective momentum-dependent potentials.
abstract: Effective classical dynamics provide a potentially powerful avenue for modeling large-scale dynamical quantum systems. We have examined the accuracy of a Hamiltonian-based approach that employs effective momentum-dependent potentials (MDPs) within a molecular-dynamics framework through studies of atomic ground states, excited states, ionization energies, and scattering properties of continuum states. Working exclusively with the Kirschbaum-Wilets (KW) formulation with empirical MDPs [C. L. Kirschbaum and L. Wilets, Phys. Rev. A 21, 834 (1980)0556-279110.1103/PhysRevA.21.834], optimization leads to very accurate ground-state energies for several elements (e.g., N, F, Ne, Al, S, Ar, and Ca) relative to Hartree-Fock values. The KW MDP parameters obtained are found to be correlated, thereby revealing some degree of transferability in the empirically determined parameters. We have studied excited-state orbits of electron-ion pair to analyze the consequences of the MDP on the classical Coulomb catastrophe. From the optimized ground-state energies, we find that the experimental first- and second-ionization energies are fairly well predicted. Finally, electron-ion scattering was examined by comparing the predicted momentum transfer cross section to a semiclassical phase-shift calculation; optimizing the MDP parameters for the scattering process yielded rather poor results, suggesting a limitation of the use of the KW MDPs for plasmas.
authors.affiliation: Department of Electrical and Computer Engineering, Michigan State University, East Lansing, Michigan 48824, USA.
authors.forename: Gautham
authors.initials: G
authors.lastname: Dharuman
authors.affiliation: Department of Electrical and Computer Engineering, Michigan State University, East Lansing, Michigan 48824, USA.|Department of Computational Mathematics, Science and Engineering, Michigan State University, East Lansing, Michigan 48824, USA.
authors.forename: John
authors.initials: J
authors.lastname: Verboncoeur
authors.affiliation: Department of Computational Mathematics, Science and Engineering, Michigan State University, East Lansing, Michigan 48824, USA.|Department of Mathematics, Michigan State University, East Lansing, Michigan 48824, USA.
authors.forename: Andrew
authors.initials: A
authors.lastname: Christlieb
authors.affiliation: New Mexico Consortium, Los Alamos, New Mexico 87544, USA.|Computational Physics and Methods Group, Los Alamos National Laboratory, Los Alamos, New Mexico 87544, USA.
authors.forename: Michael S
authors.initials: MS
authors.lastname: Murillo