George is working on a collaborative project with Prof. Véronique Gouverneur’s Research Group to study the effect of hydrogen bonding on the nucleophilicity and basicity of tetra alkyl ammononium fluoride complexes. When he’s not praying for his products to crystallise, George spends his time running the Oxford University Darts Club and playing the trombone for the Oxford University jazz orchestra.
Will is working with Nick Rees, looking into the host/guest complexes of deoxycholic acid. Using variable temperature single crystal diffraction, along with Solid State NMR and Differential Scanning Calorimetry the project is particularly focused on phase changes within the crystal as a function of temperature. When not in the lab he enjoys long lunches, and competing for the Oxford Modern Pentathlon team.
J. Appl. Cryst. (2012). 45, 1057–1060. [ doi:10.1107/S0021889812035790 ]
The traditional Waser distance restraint, the rigid-bond restraint and atomic displacement parameter (ADP) similarity restraints have an equal influence on both atoms involved in the restraint. This may be inappropriate in cases where it can reasonably be expected that the precision of the determination of the positional parameters and ADPs is not equal, e.g. towards the extremities of a librating structure or where one atom is a significantly stronger scatterer than the other. In these cases, the traditional restraint feeds information from the poorly defined atom to the better defined atom, with the possibility that its characteristics become degraded. The modified restraint described here feeds information from the better defined atom to the more poorly defined atom with minimal feedback.
Electronic reprints
Publisher’s copy
Presented by: Sebastian D. Pike & Dr. Amber L. Thompson
Research Leader: Prof. Andrew S. Weller
Published: Science
Transition metal σ-alkane complexes are key intermediates in catalytic C–H activation processes. We have used a direct crystal to crystal transition, by reaction with H2, to produce an alkane σ-complex directly. This structure is of an alkane (norbornane, NBA) σ-bound to a d8–Rh(I) metal centre, in which the chelating alkane ligand is coordinated to the pseudo-square planar metal centre through two σ-C–H bonds. Although disordered (inset), the structure was refined without restraints for the coordinated NBA. The complex reacts further over time, so many attempts were required to “catch” the crystal free from both starting material and final product.
Structure of the Month – September 2012
The second meeting of the Red Kite network will be held on Tuesday 18th September, 2012 at ISIS. Attendance will be free of charge and there will be a transport from Oxford and a drinks reception thanks to generous sponsorship from ISIS. There will also be a tour of the ISIS facility, followed by a microsymposium, comprising a number of short talks by local speakers, focussed on the use of neutrons in structural science and ending with a drinks reception and poster session.
Please check out the program for more details and email Amber L. Thompson (amber.thompson @ chem.ox.ac.uk) or Marek Jura (marek.jura @ stfc.ac.uk) BY MONDAY 10TH SEPTEMBER, if you want to come on the bus, otherwise we need a complete list of names by FRIDAY 14TH SEPTEMBER to arrange security clearance for the tours of ISIS.
ISIS experimental hall
Can you help us solve the Mystery of the Soup Dragon? It was found, abandoned (presumably by a postman) in Amber’s pigeon-hole, in a black plastic wrapper. He’s not very talkative, just gurgles very softly occasionally, but seems to be happy making a new home in Amber’s office in Chem. Cryst. Any information on the origin of The Soup Dragon would be greatly appreciated.
The Soup Dragon
An undergraduate at Pembroke, Rafal joined us for 5 weeks to carry out a summer research project between his 2nd and 3rd years. Rafal is working on the inclusion compounds of deoxycholic acid, particularly the nature of the host-guest binding and order-disorder phase transitions. When he’s not enjoying chemistry in the lab, Rafal can probably be found working hard in Pembroke College boathouse.
Summer is conference season and the members of Chem. Cryst. have been on the road to the ACA in Boston and the ECM in Bergen. In September, Kirsten will also be attending the 7th International Conference on Aperiodic Crystals, to be hosted in Cairns, Australia. Contributions include:
David J. Watkin, Richard I. Cooper & Anna Collins
Z’>1 Structures. Just a Nuisance or Something More Interesting? (ACA; Oral presentation)
Karim J. Sutton, Richard I. Cooper, Kirsten E. Christensen, Amber L. Thompson, David R. Allan & Sarah A. Barnett
Exploiting the Tunable Wavelength Capabilities of Synchrotron Radiation for Small Molecule Single Crystal X-ray Crystallography (ACA; Prize winning oral presentation)
Richard I. Cooper
CRYSTALS: Teaching an Old Dog New Tricks (ACA; Oral presentation)
Amber L. Thompson
When Small Molecules Get Large – A Journey into the Unknown (ECM; Oral presentation)
Anthony Linden & Amber L. Thompson
Hot topics and Structures in Molecular Chemistry (ECM; Microsymposium)
Kirsten E. Christensen & Amber L. Thompson
New Challenges in Chemical Crystallography (Aperiodic; Oral presentation)
Along the bryggen in Bergen
In Bergen
Something smells a little fishy
A BIG fishy!
It really *IS* that expensive in Norway!
Albert Einstein or Edvard Greig?
Norwegian Humour
Congratulations to Karim Sutton, who has been awarded a Margaret C. Etter Student Lecturer Award at the recent American Crystallographic Association annual meeting in Boston.
He presented his recent research determining oxidation states in mixed-valent materials using tunable synchrotron radiation on Diamond beamline I19.
The awards were established to honour the memory of Professor Etter (1943-1992), who was a major contributor to the field of organic solid-state chemistry.
The results have just been announced for the latest round of applications to the John Fell Oxford University Research Fund. Our application for funding for meetings for the Red Kite network over the next three years was successful, which is excellent news and should secure its immediate future.