For his Part II year, Karim worked in Chem. Cryst. studying ion binding in rotaxanes (in collaboration with Paul Beer’s research group). He has now returned to do a D. Phil. spending part of his time at Diamond Light Source. When he’s not at Diamond he can be found playing darts or cricket for Worcester College.
Karim is a founder member of the Quiztallographers.
Nia’s Part II project is focused on the preparation and systematic study of thiosemicarbazone complexes by single crystal X-ray diffraction. When not in the lab she may be found listening to music at live venues, or perhaps sampling some of Oxford’s fine real ales.
David is exploring the different ways of describing ring puckering and conformation. By using data in the CSD and avoiding the lab as much as possible, he hopes to create an amalgamated approach to defining ring puckering and conformation that could be implemented in refinement software. If he isn’t hiding in the CRL basement he’s most likely to be found doing some from of college sport.
J. Appl. Cryst. (2011), 44, 1017-1022.   [ doi:10.1107/S0021889811034066 ]
A summary of the features for investigating absolute structure available in the crystallographic refinement program CRYSTALS is presented, together with the results of analyses of 150 light-atom structures collected with molybdenum radiation carried out with these tools. The results confirm that the Flack and Hooft parameters are strongly indicative, even when the standard uncertainties are large compared to the thresholds recommended by Flack & Bernardinelli [J. Appl. Cryst. (2000), 33, 1143–1148].
Electronic reprints
Publisher’s copy
Presented by:Â Andrew B. Cairns & Dr. Amber L. Thompson
Research Leader:Â Dr. Andrew L. Goodwin
Published:Â Journal of the American Chemical Society (cover article)
Negative Linear Compressibility (NLC) is where a material unusually expands in one direction under increasing pressure. Potassium manganese dicyanoargentate exhibits the largest NLC over an extended range of any known material: ‑12.0(8) TPa–1. The structural features are both beautiful and unique to cause this effect. [MnN6] octahedra are connected via almost linear ‘floppy’ NC–Ag–CN units, with K+ ions positioned above and below alternating Ag3 Kagome triangles (top). The lattice framework is made up of three independent interpenetrated a-Polonium nets (bottom right), with only weak argentophilic interactions between the nets. Variable temperature SCXRD was carried out in Oxford and the variable pressure work was the first pressure experiment carried out on WISH at ISIS.
Structure of the Month – September 2011