The innovation engine for new materials

Radioactive? Tick; Toxic? Tick; Explosive? Tick. What could possibly go wrong?

Seminar Group: 


Brendan J. Kennedy


School of Chemistry, The University of Sydney
Sydney, NSW 2006, Australia


Tuesday, June 13, 2017 - 3:00pm


MRL Room 2053


Prof. Ram Seshadri

Innovation drives science, and major national facilities such as synchrotrons and neutron sources are often a critical tool in this. Consequently many experiments done at major facilities are pioneering and/or unique. Despite the impression we may form when completing a Risk Assessment prior to an experiment, Synchrotrons are the antipathy of the nanny state. For example the Australian Synchrotron frequently allows experiments under extreme conditions with extremely reactive or toxic materials. As the title says what could possibly go wrong when heating a radioactive material to 1000 degrees under a hydrogen atmosphere?

In this presentation I will describe our journey to the riskier side of chemistry, looking at structural transformations in uranium, technetium and osmium oxides. Each of these elements present unique handling challenges that are further compounded since we are interested in the response of the materials to changes in temperature and environment. Whilst my tool of choice is generally high resolution powder diffraction there is often the need to supplement this with spectroscopic information; moving hazards from one beamline to thenext, always with the hope of being allowed back.

[1] E. Reynolds, M. Avdeev, G. J. Thorogood, F. Poineau, K. R. Czerwinski, J. A. Kimpton, M. Yu, P. Kayser, and B. J. Kennedy, Structure and magnetism in Sr1−xAxTcO3 perovskites: Importance of the A-site cation, Phys. Rev. B 2017 95, 054430.
[2] G. Murphy, B. J. Kennedy, J. Kimpton, Q.-F. Gu, B. Johannessen, et al.: Non stoichiometry in strontium uranium oxide: Understanding the rhombohedral – orthorhombic transition in SrUO4, Inorg. Chem. 2016 55, 9329–9334.
[3] P. Kayser, S. Injac , B. J. Kennedy, T. Vogt, M. Avdeev, H. E. Maynard-Casly and Z. Zhang, Structural and magnetic properties of the osmium double perovskites Ba2–xSrxYOsO6 Inorg. Chem. 2017 56 in press.