Dr. Richard Heenan is a senior scientist at the ISIS Facility and leads the Small Angle Neutron Scattering (SANS) team. Following a degree and PhD at Reading and Postdoctoral positions in Michigan and Canterbury Kent, he started at ISIS in 1984, to complete the construction of the LOQ, SANS, beam line (http://www.isis.stfc.ac.uk/instruments/loq/ ). Now he is widely regarded as a global expert in the fields of small angle scattering instrumentation, SANS data reduction and fitting, with contributions to over 260 scientific publications (http://epubs.cclrc.ac.uk/search?mpp=25&q=heenan&all=Y ).
SANS is often used in conjunction with a range other techniques to characterise sample materials on distance scales of 1 to 100 nm. ( 100 nm = 10-7 m = one ten thousandth of a millimetre.) These distances are larger than individual atoms but still smaller than can be seen with optical microscopes. Since SANS provides a direct structural observation, albeit a Fourier transform into reciprocal space, rather than a real space “photograph”, it is usually a key technique. Rather than measure just a few structures, samples are studied under a whole range of different compositions, or under different conditions of say temperature, pH or shear rate, in order to see how a system as a whole behaves.
Interests in the development of the SANS technique and data fitting has led to a wide range of collaborations with university groups. Training many PhD students, and their supervisors, how to analyse small angle scattering data has led to much greater exploitation of hard won beam time, and a better appreciation in the research community of the benefits of pulsed neutron sources.
Research and development interests
The main area of expertise has been to use his own program FISH (available from http://www.small-angle.ac.uk/small-angle/Software.html ) on data from solutions of nanoscale particles such as surfactant micelles, microemulsion droplets, viral capsids, and block copolymer aggregates. FISH enables complex models of small angle scattering for multi-shell or mixed particle shapes to be quickly constructed and tested on data. Simultaneous fits are possible to multiple data sets from different instrument configurations, contrast variation series or combined X-ray and neutron small-angle data. Some of the features of FISH along with many different ones are now also available in the more recent SASVIEW code from http://sourceforge.net/projects/sasview/ , which ISIS is helping to support.
SANS often provides results that are directly relevant for applications, whether for domestic personal care products, or say a prototype block copolymer system that may soon be used to deliver an anti-cancer drug. It is a pleasure to be able to discuss SANS ideas with or collaborate with a wide range of researchers from different fields; new enquiries are always welcome.