Full-potential multiple scattering theory with space-filling cells for bound and continuum states

Abstract

Abstract. We present a rigorous derivation of a real space Full-Potential MultipleScattering-Theory (FP-MST) that is free from the drawbacks that up to now have impaired its development (in particular the need to expand cell shape functions in spherical harmonics and rectangular matrices), valid both for continuum and bound states, under conditions for space-partitioning that are not excessively restrictive and easily implemented. In this connection we give a new scheme to generate local basis functions for the truncated potential cells that is simple, fast, efficient, valid for any shape of the cell and reduces to the minimum the number of spherical harmonics in the expansion of the scattering wave function. The method also avoids the need for saturating 'internal sums' due to the re-expansion of the spherical Hankel functions around another point in space (usually another cell center). Thus this approach, provides a straightforward extension of MST in the Muffin-Tin (MT) approximation, with only one truncation parameter given by the classical relation l max = kR b , where k is the electron wave vector (either in the excited or ground state of the system under consideration) and R b the radius of the bounding sphere of the scattering cell. Moreover, the scattering path operator of the theory can be found in terms of an absolutely convergent procedure in the l max → ∞ limit. Consequently, this feature provides a firm ground to the use of FP-MST as a viable method for electronic structure calculations and makes possible the computation of x-ray spectroscopies, notably photo-electron diffraction, absorption and anomalous scattering among others, with the ease and versatility of the corresponding MT theory. Some numerical applications of the theory are presented, both for continuum and bound states.

X-ray absorption spectra of graphene and graphene oxide by full-potential multiple scattering calculations with self-consistent charge density

“…Here we give a brief summary of our FPMS method developed previously by some of us [7]. The real-space FPMS theory with spacefilling cells used here is valid both for continuum and bound states and contains only one truncation parameter -lmax, the maximum angular momentum of spherical wave basis.…”

“…Here we report XANES calculations of ideal and defective graphene, graphene oxide and diamond, using the real-space full potential multiple scattering (FPMS) theory with arbitrarily truncated space-filling cells [7,8].…”

Synthesis, structural studies and biological activity of new Cu(II) complexes with acetyl derivatives of 7-hydroxy-4-methylcoumarin

“…However, this type of potential does not work properly for the flat geometry, which is the case for the considered Cu(II) complexes. In order to perform reliable calculations the FPMS code developed by Hatada and coworkers [31,32] was used. The real part of Hedin-Lundqvist potential (HL) was employed [33].…”

A Bridge between Conceptual Frameworks

“…Calculations are now possible within both the "muffintin" and "non-muffin-tin" approximations (Joly 2001;Hatada et al 2010), although a major, unfortunately still incompletely worked out problems, first evidenced by natoli et al (1986) and studied by Gunnella et al . Calculations are now possible within both the "muffintin" and "non-muffin-tin" approximations (Joly 2001;Hatada et al 2010), although a major, unfortunately still incompletely worked out problems, first evidenced by natoli et al (1986) and studied by Gunnella et al .…”