Calculation of mean excitation energy and stopping cross section in the orbital local plasma approximation

Journal Article · Mon Jan 01 00:00:00 EST 1990 · Physical Review, A (General Physics); (USA)

DOI:https://doi.org/10.1103/PhysRevA.41.220· OSTI ID:7102409

Meltzer, D E; Sabin, J R; Trickey, S B ^[1]

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1. Quantum Theory Project, Department of Physics and Department of Chemistry, University of Florida, Gainesville, Florida 32611 (USA)

Extension of the kinetic theory of stopping, in the Oddershede-Sabin (OS) (At. Data Nucl. Data Tables 31, 275 (1984)) orbitally decomposed form, from gas phase to films and crystals generates the need for orbital mean excitation energies calculated within the local-spin-density approximation (LSDA) to density-functional theory (DFT), the preeminent theoretical model for such extended systems. In LSDA, the orbitals and orbital energies used in the construction of the electron density {rho} have no standing for estimation or calculation of excitation energies. As an alternative we propose an orbital density generalization of the local plasma approximation (LPA) of Lindhard and Scharff (K. Dan. Vidensk. Selsk. Mat. Fys. Medd. 27, No. 15 (1953)) that we test by calculation of mean excitation energies {ital I}{sub {ital k}} for each atomic orbital {ital k} within the LSDA for all atoms with {ital Z}{lt}37. Stopping cross sections for a representative sample (about half) of these elements have been calculated using these {ital I}{sub {ital k}} values. The results do not differ substantially from those of OS (who used {ital I}{sub {ital k}} values from Dehmer, Inokuti, and Saxon (Phys. Rev. A 12, 102 (1975)); Inokuti, Baer, and Dehmer ({ital ibid}. 17, 1229 (1978)); Inokuti, Dehmer, Baer, and Hanson ({ital ibid}. 23, 95 (1981))), with the discrepancy generally less than 15%.

• OSTI ID: 7102409
• Journal Information: Physical Review, A (General Physics); (USA), Vol. 41:1; ISSN 0556-2791
• Country of Publication: United States
• Language: English

Related Subjects

73 NUCLEAR PHYSICS AND RADIATION PHYSICS
CHARGED-PARTICLE TRANSPORT THEORY
STOPPING POWER
CROSS SECTIONS
CRYSTALS
ENERGY LOSSES
EXCITATION
FILMS
GASES
HEAVY IONS
CHARGED PARTICLES
ENERGY-LEVEL TRANSITIONS
FLUIDS
IONS
LOSSES
TRANSPORT THEORY
654001* - Radiation & Shielding Physics- Radiation Physics
Shielding Calculations & Experiments