Postgraduate Seminar Series Thursday 24th January Room 564 5pm Silicon Related Defects in Diamond: What electronic paramagnetic resonance (EPR) can tell us By Andy Edmonds It has been known since 1995 that a defect exists in diamond which can be attributed to the accidental contamination of the material with silicon. However, to-date no published experimental work has conclusively determined the structure and symmetry of this defect. In this talk the results of EPR studies of silicon-containing diamonds will be used to elucidate the structure and provide some insight into formation mechanisms of this centre. An Automatic Lock-in? Why Growing Crystals is a Mystery Game By Dean Keeble Start the fans, please! An overview of an ongoing single crystal study of the stacked perovskite “Aurivillius” solid solution SrBi2NbxTa(1-x)O9 is presented. These materials are reported to be ferroelectric based on recent powdered studies. The benefits of single crystal work over powders are summarised, and a comparison of single crystal and powder data is also presented. The postgraduate seminar series is a series of informal talks run by postgraduates for postgraduates. All postgraduates are welcome and refreshments are always provided!