AOFSRR 2015 in conjunction with User Meeting 2015

FDMX: Full-Potential Calculations of EXAFS for Extraction of Structural, Thermal, and Electronic Properties from Absolute Accuracy Measurements

26 Nov 2015, 13:30

45m

Exhibition space (National Centre for Synchrotron Science)

Board: BT-07

Poster Beamlines, Instrumentation and Techniques Poster Session 1

Speakers

Prof. Christopher Thomas Chantler (University of Melbourne)Dr Jay D Bourke (U Melbourne)

Description

We present the new computational package FDMX; a full-potential code for accurate robust calculations of x-ray absorption fine structure across all energies from below the edge to the smooth atom-like absorption region. Full-potential modeling of condensed matter systems is a critical tool for analysis of x-ray absorption near-edge structure (XANES) spectra [1,2]. Despite demonstrated advantages in the low-energy regime [3], these tools are still not generally applied to EXAFS analysis. We present here the new package FDMX, a development of the Finite Difference Method for Near-Edge Structure (FDMNES) package [2], for use in the calculation of extended XAFS spectra. FDMX features new implementations of thermal and electron scattering parameters [4], core-hole and outer-shell absorption effects. FDMX calculates high-accuracy XAFS spectra for large energy ranges in both elemental and complex molecular systems. Material parameters such as bond lengths, electron inelastic mean free paths [5], and Debye-Waller factors [6] may be extracted using full-potential modeling. [1] P Blaha etal., Comput. Phys. Commun. 59 339 (1990) [2] Y Joly, Phys. Rev. B 63 125120 (2001) [3] JL Glover, CT Chantler, AV Soldatov, G Smolentsez and MC Feiters, AIP Conf. Proc. 882(2007)625 [4] JD Bourke, CT Chantler, J. Phys. Chem. Lett. 6(2015)314 [5] JD Bourke, CT Chantler, Phys. Rev. Lett. 104(2010)206601 [6] LJ Tantau, CT Chantler, JD Bourke, MT Islam, AT Payne, NA Rae, CQ Tran, J. Phys.Condens.Mat.27(2015)266301