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Multipolar Expansions for Multiple Scattering Theory

Published online by Cambridge University Press:  25 February 2011

R. G. Brown  and
M. Ciftan
R. G. Brown
Affiliation:
Duke University Physics Department, Durham, NC 27707; emial: rgb@pliy.duke.edu
M. Ciftan
Affiliation:
Duke University Physics Department, Durham, NC 27707 or Army Research Office, Research Triangle Park, Durham, NC
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Abstract

A simple derivation (based on a derived identity of integral equation theory) of fully separable, non–muffin–tin multiple scattering theory is presented. Three multipolar representations have been proposed for use in this theory: the original representation by Williams and Morgan, a more recent one by Brown and Ciftan, and a “Bloch periodic” representation by Badralexe and Freeman (which was addressed in earlier work). We study the properties of the Williams and Morgan representation in the context of the 2D empty square lattice, where the representation of Brown and Ciftan is manifestly exact and correct (so that MST derived in terms of it is a “natural” theory). We show that the representation of Williams and Morgan contains an explict divergence predicted by its implicit use of a wrong-order Green's function expansion but that MST expressed in terms of this representation is still a fairly good asymptotic approximation to the formally exact theory.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 253: Symposium V – Application of Multiple Scattering Theory to Materials Science , 1991 , 173
Copyright
Copyright © Materials Research Society 1992

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References

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