Recent developments in the application of X-ray and neutron reflectivity to soft-matter systems

Many interesting physical, chemical and biological phenomena occur at interfaces between nanometre-scale layers of soft condensed matter. These often complex systems lend themselves to be studied by X-ray reflectivity (XRR) and neutron reflectivity (NR). The application of these techniques to such systems is extremely widespread and provides unique insights into their structure and dynamics. This review presents a snapshot of recent activity in this research area and identifies trends in the application of XRR and NR to novel, unusual or highly complex sample systems. Although the majority of research using these techniques is investigating variations on 'traditional' systems, supported by progress in instrumentation, advance sample environment and computational tools, NR and XRR have begun to produce singular insights into areas such as atmospheric science, real biological systems (cells and bacteria), oil-water interfaces or industrial problems (rheology, packaging or durability of nanomaterials).