Beyond crystallography: the study of disorder, nanocrystallinity and crystallographically challenged materials with pair distribution functions
Chemical Communications, 2004, (7), 749-760

Studying the structure of disordered and partially ordered materials is notoriously difficult. Recently, significant advances have been made using the atomic pair distribution function (PDF) analysis of powder diffraction data coupled with the use of advanced X-ray and neutron sources and fast computers. This article summarizes some of the more spectacular successes of this technique in studying the structure of complex materials and compounds. Our objective is to make the PDF analysis technique familiar to the scientific community by describing its methodologies and highlighting its potential in solving structural characterization problems that are intractable by any other technique available to this community e.g. single crystal diffraction, Rietveld refinement of powder diffraction data and extended X-ray absorption fine structure analysis (EXAFS).

Underneath the Bragg Peaks: Structural Analysis of Complex Materials
(Pergamon Materials Series, V. 7)

Atomic pair distribution function (PDF) analysis is a unique and powerful method to study the atomic structure of nano-materials. This book focuses on the structural determination of crystalline solids with extensive disorder. Well-established methods exist for characterizing the structure of fully crystalline solids or fully disordered materials such as liquids and glasses, but there is a dearth of techniques for the cases in-between, crystalline solids with internal atomic and nanometer scale disorder. The book discusses how to fill the gap using modern tools of structural characterization. While this subject might sound rather narrow, the fact is that today this problem is encountered in the structural characterization of a surprisingly wide range of complex materials of interest to modern technology and is becoming increasingly important.

Rapid-acquisition pair distribution function (RA-PDF) analysis
J. Appl. Cryst. (2003). 36, 1342-1347

Materials with different structural complexities can be studied using recently developed RA-PDF technique. This technique utilizes the advantage of an image-plate (IP) detector coupled with high-energy synchrotron radiation to perform the PDF analysis. Medium-high real-space resolution PDF data analysis from crystalline materials has recently been performed using data with high probed momentum transfer collected by an IP detector. Comparable or even better statistics than from conventional X-ray measurements can be achieved with significantly shorter counting times. The diffraction patterns show good counting statistics, with measuring time from one to tens of seconds. The PDFs obtained are of high quality. The new combination of a real-space probe and fast counting time opens up a broad field for future applications to a wide variety of materials of both scientific and technological interest. For example, PDF methods could be used to study structural changes under in situ conditions, and the time development of chemical reactions and biological systems over short time scales of seconds may be studied.

For further information about the NIRT- Structure of Nanocrystals work, please contact Professor Simon Billinge (billinge@pa.msu.edu).