MS36-P31 A Systematic Study of Radiation Damage in Transition Metal Chloride Complexes with 1,5-cyclooctadiene Ligands using Diffraction and Spectroscopy. Claire Murray (Diamond Light Source, Didcot, United Kingdom) Alex Ganose (Chemistry, University College London, London, United Kingdom) Anna Regoutz (Materials, Imperial College London, London, United Kingdom) David Scanlon (Chemistry, University College London, London, United Kingdom) Amber Thompson (Chemistry, University of Oxford, Oxford, United Kingdom)email: metal chloride complexes with 1,5-cyclooctadiene ligands have a variety of applications as catalysts or precatalysts in e.g. hydrogenation and hydrogen-transfer reactions.(1) However, their interactions with X-rays has, to date, been assumed to be non-destructive with no reports in the literature of behaviours indicating radiation damage such as intensity loss in diffraction peaks or peak broadening. Interaction of X-rays with the crystal lattice is an effect that causes well-known problems in biological systems,(2) but this effect is only formally starting to be recognised in chemical crystallography. A survey of the effects of radiation damage to small molecule single crystals(3) demonstrated a relationship between the damage and the intensity of the source. The improving intensity of sources both at central facilities and for in-house instruments is increasing awareness of radiation damage, with a particular lack of understanding for small molecule crystallographers and spectroscopists currently complicating data collection. A series of compounds have been studied where M = Ir, Rh and Cu to, quite literally, shed light on the chemical changes resulting from X-ray exposure via structural and electronic insights. The combination of powder X-ray diffraction, single crystal X-ray diffraction, computational studies and X-ray photoemission spectroscopy reveal the impact of X-ray radiation on these materials in great detail and also provide insight into the importance of identifying appropriate data collection techniques for experiments.

(1) Crabtree, R. H., Morehouse, S. M. & Quirk, J. M. (2007), Inorganic Syntheses, J. M. Shreeve (Ed.). doi:10.1002/9780470132555.ch50

(2) Blake, C.C.F & D. C. Philips, (1962), Symposium of the International Atomic Energy Agency, Vienna, Austria, p. 183.

(3) Abrahams, S.C.,(1973) Acta Crystallogr., Sect. A, 29, 111.
Keywords: X-rays, Catalysts, Synchrotron