Amber L. Thompson

Apr 012011
 

Presented by: Nicholas G. White & Dr. Fabiola Zapata
Research Leader: Prof. Paul D. Beer
Published: Journal of the American Chemical Society

Both the mixed bromide/PF6 and mixed iodide/PF6 salt of this bis-iodoimidazolium macrocycle crystallize in the unusual cubic spacegroup I m -3 (there are currently only six organic structures in this spacegroup in the CSD).  The macrocycle binds anions strongly and selectively in competitive methanol/water solvent mixtures, with anions being bound solely by halogen-bonding interactions.  In the solid state, the both the bromide and iodide salts of the macrocycle exist as a dimer, with two macrocycles each pointing at two halide anions.  Experiments are being undertaken to see if this arrangement occurs in solution.

Structure of the Month - April 2011

Structure of the Month – April 2011

Mar 172011
 

Keith Prout died quite suddenly in September 2007 after a short illness.

Although he had been officially retired for several years, he was continuing an active research program with Nick Rees combining X-ray and NMR studies.  X-ray structure analysis gives information about disorder and thermal vibrations in crystals. When combined with solid state NMR a complete dynamic profile of the crystal can be obtained.

Previous studies of penicillins, ansa-titanocenes and tri-ethyl phosphate molecular complexes with various hosts suggest a variety of molecular motions in addition to the ‘translation-libration-screw’ motion derived from the crystallographic atomic displacement parameters.  He also studied  order/disorder phase transitions, molecular motion and chiral selectivity in deoxycholic acid molecular complexes.

Mar 162011
 

Dr. Violeta JevtovicVioleta is an assistant professor in the Chemistry Department at the University of Novi Sad, Serbia.  She obtained her Ph.D. in coordination chemistry studying the synthesis, structure and biological activity of transition metal compounds and visited for a few months to learn more about crystallography.

Mar 162011
 

Terry worked for the Atomic Energy Research Establishment, Harwell for many years before he joined Chem. Cryst.

Terry was one of the pioneers of the use of neutron scattering in the United Kingdom and a founder member of the BCA.  Although interested in many areas of crystallography, his particular specialities are neutron scattering studies of crystal structures and lattice dynamics of inorganic materials. Recent interests are the determination of the crystal structures of the oxides of uranium and the nature of the phase transitions in U4O9. The oxide studies are undertaken in collaboration with Frederico Garrido of the University of Paris, Lech Nowicki of the Soltan Institute of Nuclear Physics, Warsaw and Alberto Albinati of the University of Milan.

The author of a number of highly regarded books, there is a prize awarded in his honour sponsored by the Institute of Physics and the Royal Society of Chemistry.

Mar 162011
 

Emma’s research is focussed on developing a better understanding of the solid state.  She is using a three pronged attack, studying the crystallisation of chalcones; examining the effect of temperature on a material that undergoes a phase transition, and investigating the World’s Favourite Space Group, P21/c.  She is using a wide range of probes, including the Cambridge Structural Database, dSNAP, Laue Diffraction, Solid State NMR and Variable Temperature Single Crystal Diffraction as well as collecting data at Diamond.  When not fighting to grow crystals or preparing dinner for the team at Diamond, she enjoys dancing, but refuses to perform for the group.

Mar 162011
 

Jeremy’s research revolves around using various techniques (NMR, crystallography and DFT calculations) to provide information about exactly where hydrogen atoms are located in crystal structures, and exploring the merits and shortcomings of the various techniques for this purpose. When he isn’t trying to persuade a supercomputer to calculate what he wants, he enjoys playing the trumpet with the Oxford University Big Band, plays squash and designs prize-winning posters.