DAWN

DAWN, the Data Analysis WorkbeNch, is an Eclipse based application for scientific data analysis. It comes with a range of tools for visualization (1D, 2D and 3D), code development environments (for Python, Jython and Eclipse plug-ins) as well as processing workflows with visual algorithms for analyzing scientific datasets. It is primarily developed at Diamond Light Source, but external contributions are most welcome! DAWN is distributed freely and is released under the Eclipse Public License.

Demeter

Demeter is a comprehensive system for processing and analyzing X-ray Absorption Spectroscopy data. It contains several packages such as Athena, Artemis and Hephaestus, which are widely used in the XAFS community.

DL_EXCURV (formerly EXCURVE)

Data analysis of EXAFS spectra using the fast spherical wave method. It provides an integrated environment for the analysis of EXAFS spectra while delivering a platform for the fast spherical wave method. The current version is based on this method for single scattering, but uses the method of Lee and Pendry (1975) for the exact polarisation dependent theory. Multiple scattering has options to use several methods. It allows fitting of both background-subtracted, and normalised total absorbance spectra. In the latter case the program calculates the atomic contribution of the spectrum (whole-spectrum fitting). The purpose of the program is to find a structural model of a material which agrees with the available XAFS spectra. This program (without GUI) was formerly called EXCURVE and is the one installed at the ESRF

FDMNES

The aim of the FDMNES project is to supply to the community a user friendly code to simulate x-ray spectroscopies, linked to the real absorption (XANES, XMCD) or resonant scattering (RXD) of the synchrotron radiation. This ab initio approach, wants to eliminate all the methodological parameters. First mainly mono-electronic, using the functionnal density theory (DFT), it includes now multi-electronics advances with the use of the time dependant DFT (TD-DFT) for a better taking into account of the excited states linked to the photon-matter interaction. It includes also the Hubbard correction (LDA+U) for a better description of the so called correlated materials.

FEFF9

Condensed matter code for modelling x-ray and electron spectroscopies and materials properties. FEFF is an automated program for ab initio multiple scattering calculations of X-ray Absorption Fine Structure (XAFS), X-ray Absorption Near-Edge Structure (XANES) and various other spectra for clusters of atoms. The code yields scattering amplitudes and phases used in many modern XAFS analysis codes, as well as various other properties. in FEFF9 there are several new spectroscopies which can be calculated with FEFF 9, including electron energy loss spectra (EELS) and non-resonant inelastic x-ray scattering (NRIXS). In addition, there are a variety of improvements. These include; (1) ab initio Debye-Waller factors; (2) improved treatment of inelastic losses; (3) an improved treatment of the core-hole interaction; and (4) more accurate treatment of crystalline systems with k-space calculation of the Green's function. FEFF9 comes with the JFEFF GUI.

GNXAS

The GNXAS package is a computer code for EXAFS data analysis based on multiple-scattering (MS) calculations and a rigorous fitting procedure of the raw experimental data. The main characteristic of the software are: + atomic phase shifts calculations in the muffin-tin approximation based on atom self-consistent relativistic calculations. Account for the neighbors is taken. + Inclusion of inelastic losses through complex Hedin-Lundqvist potential. + Calculation of MS signals associated with two, three, and four atom configurations using advanced algorithms. Use of an advanced fitting procedure that allows: + to fit simultaneously any number of spectra containing any number of edges, + to use directly the raw data without any pre-analysis, + to account for complex background multi-electron excitation features, + to use various model peaks for the pair, triplet and quadruplet distribution functions, including non Gaussian models and extreme cases. In all cases absolute parameters can be fitted, - to treat liquid phase or disordered systems and extract reliable g(r) functions in the short range, - to perform a rigorous statistical error analysis and plot two-dimensional correlation maps, - to provide a flexible scientific tool for EXAFS data analysis where the user has access to every stage of the calculation. - full modularity that makes easy to interface parts of the GNXAS software with other available software.

MXAN

MXAN performs a quantitative analysis of the XANES energy range. This is based on a comparison between experimental data and many theoretical spectra that are calculated by varying selected structural parameters of an initial putative structure, i.e. a well defined initial geometrical configurations around the absorber. Hundreds of different geometrical configurations are needed to obtain the best fit of the experimental data. The calculations are performed in the energy space without involving any Fourier transform algorithm; polarized spectra can be easily analysed because the calculations are performed within the full multiple scattering approach. Recently, MXAN has been developed in the framework of the multiple scattering theory and successfully applied to the analysis of several system, both in solid and liquid state. The MXAN procedure,encompasses also the phenomenological broadening and the electronic charge fitting.

P

Combined EXAFS and XRPD data analysis with EXAFS full multiple scattering calculations and whole-spectrum fitting. A code designed to maximise the usefulness of the EXAFS technique in the investigation of crystalline materials which powder diffraction (PD) methods could not uniquely resolve. The program retains many of the features of EXCURVE (s. the related web pages) and provides most of the PD features of the program GSAS. For EXAFS this includes full multiple scattering calculations and whole-spectrum fitting, but at present it cannot deal with EXAFS polarisation dependence. PD calculations currently exclude calculation of the thermal diffuse scattering contribution, which is included in the background.

Software