xPDFsuite - an end-to end software solution for atomic pair distribution function analysis

This suite of algorithms and software, named xPDFsuite, provides an end-to end software solution for PDF analysis. It includes code to integrate 2D powder diffraction patterns (if required), to convert the resulting 1D powder patterns to reduced structure functions and the PDF, to interrogate those models using correlation analysis and to model the PDF using the popular PDFgui program.

PDF characterization of materials including drugs and industrial materials in their amorphous and nanocrystalline and liquid states

Many materials of interest in next generation technologies are nanostructured or disordered. Examples include battery electrodes and electrolytes, supercapacitors, nanoparticles with interesting optical properties and many drugs in the discovery pipeline that have limited solubility in the crystalline state.

Approaches using total scattering pair distribution function analysis of x-ray and neutron diffraction data facilitate visualization of pharmaceutical and industrial compounds' structures. This is one of the few possible ways to obtain direct structural information about amorphous and nanocrystalline materials for which conventional XRD approaches don't work.

This software implements a number of recent developments in the data analysis and modeling of PDFs derived from X-ray experiments which may be carried out at synchrotron or laboratory sources that allow for highly automated and straightforward processing. The software includes a full-featured graphical user interface and is designed for the latest generation of studies that involve often many hundreds or thousands of datasets. The software runs on laptops and workstations running windows, mac OSX and linux.

XRD Algorithms Faster, Easier To Use For Analysis of Multiple XRD Datasets

Improving upon an earlier version of the software, xPDFsuite is programmed in Python instead of IDL (Interactive Data Language), making it more portable than its predecessor. The software also gives the user robust and reliable total scattering pair distribution functions by specifying a very small number of input parameters.

Unlike other programs for obtaining the pair distribution function, the software is exceptionally easy to learn and use. This increases the range of people who can use it, decreases training costs, and speeding up workflow. xPDFsuite also permits users to run multiple data sets using the same input file, allowing for batch processing in fractions of a second.

Tests of this technology using input XRD data obtained from several classes of materials with different structures (e.g., crystalline, nanocrystalline, nanoparticle, and amorphous) have indicated that the method performs favorably and accurately compared to existing total scattering pair distribution function algorithms.

Applications:

• Structural characterization of crystalline, nanocrystalline, amorphous or nanoparticle materials, including inorganics, polymers and pharmaceuticals.
• Materials development guidance
• Testing of compounds to ensure consistency during development
• Submission for federal agency (e.g., FDA) approval
• Patent application filing
• Intellectual property infringement defense
• Stability studies, e.g., to determine shelf lifetime of drugs

Advantages:

• First viable means of characterizing the structure of amorphous or nanocrystalline compounds
• Yields information that makes the development of amorphous or nanocrystalline materials much more feasible
• In contrast to earlier algorithms, the technology can compute the total scattering pair distribution function in several microseconds.

Lead Inventor:

Simon Billinge, Ph.D, Professor of Materials Science, Applied Physics, Applied Mathematics at Columbia University and Physicist, X-Ray Scattering Group at Brookhaven National Laboratory. Professor Billinge was a Fulbright Scholar for the academic year 2011-2012. He has received many other awards including the J. D. Hanawalt Award and University Distinguished Professor. His research specialty is nanoscale structure-property relationships studied using x-ray and neutron scattering techniques. Billinge is a leader in developing atomic pair distribution function method applied to complex materials that can be used in the study of energy, catalysis, environmental remediation, and pharmaceuticals.