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Title: Full potential multiple scattering theory

Abstract

A practical method for performing self-consistent electronic structure calculations based upon full-potential multiple-scattering theory is presented. Solutions to the single site Schroedinger equation are obtained by solving coupled channel integral equations for a potential which is analytically continued out to the circumscribing sphere. This potential coincides with the full cell potential inside each atomic cell. Scattering matrices and wavefunctions for the full cell potential are obtained from surface Wronskian relations. The charge density is obtained from the single particle Green`s function. This Green`s function is computed using the cell scattering matrices and wavefunctions using the layer multiple scattering theory. Self consistent solutions require a solution at each iteration to the Poisson equation. The Poisson equation is solved using a variational cellular method. In the approach a local solution to each cell is augmented by adding a series of regular harmonics (solutions to Laplace`s equation). Minimizing the coulomb energy, subject to continuity of the potential across all cell boundary provides an expression for the coefficients of the regular harmonics. This method is applied to BCC Nb. Calculated properties converge well in angular momentum and show comparable accuracy to full potential linearized muffin-tin orbital calculations.

Authors:
 [1]
+ Show Author Affiliations
  1. Tulane Univ., New Orleans, LA (United States). Dept. of Physics
Publication Date:
Research Org.:
Lawrence Livermore National Lab., CA (United States); Tulane Univ., New Orleans, LA (United States). Dept. of Physics
Sponsoring Org.:
USDOE, Washington, DC (United States)
OSTI Identifier:
10195709
Report Number(s):
UCRL-CR-116369
ON: DE95003197;; TRN: AHC29430%%76
DOE Contract Number:
W-7405-ENG-48
Resource Type:
Technical Report
Resource Relation:
Other Information: PBD: 20 Oct 1994
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; NIOBIUM; LATTICE PARAMETERS; ELASTICITY; BCC LATTICES; ELECTRONIC STRUCTURE; CALCULATION METHODS; MUFFIN-TIN POTENTIAL; SELF-CONSISTENT FIELD; ALGORITHMS; THEORETICAL DATA; 360102; 360103; STRUCTURE AND PHASE STUDIES; MECHANICAL PROPERTIES

Citation Formats

MacLaren, J.M. Full potential multiple scattering theory. United States: N. p., 1994. Web. doi:10.2172/10195709.
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MacLaren, J.M. Full potential multiple scattering theory. United States. doi:10.2172/10195709.
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MacLaren, J.M. Thu . "Full potential multiple scattering theory". United States. doi:10.2172/10195709. https://www.osti.gov/servlets/purl/10195709.
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@article{osti_10195709,
title = {Full potential multiple scattering theory},
author = {MacLaren, J.M.},
abstractNote = {A practical method for performing self-consistent electronic structure calculations based upon full-potential multiple-scattering theory is presented. Solutions to the single site Schroedinger equation are obtained by solving coupled channel integral equations for a potential which is analytically continued out to the circumscribing sphere. This potential coincides with the full cell potential inside each atomic cell. Scattering matrices and wavefunctions for the full cell potential are obtained from surface Wronskian relations. The charge density is obtained from the single particle Green`s function. This Green`s function is computed using the cell scattering matrices and wavefunctions using the layer multiple scattering theory. Self consistent solutions require a solution at each iteration to the Poisson equation. The Poisson equation is solved using a variational cellular method. In the approach a local solution to each cell is augmented by adding a series of regular harmonics (solutions to Laplace`s equation). Minimizing the coulomb energy, subject to continuity of the potential across all cell boundary provides an expression for the coefficients of the regular harmonics. This method is applied to BCC Nb. Calculated properties converge well in angular momentum and show comparable accuracy to full potential linearized muffin-tin orbital calculations.},
doi = {10.2172/10195709},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Thu Oct 20 00:00:00 EDT 1994},
month = {Thu Oct 20 00:00:00 EDT 1994}
}
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Technical Report:
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DOI:  10.2172/10195709
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