Nov 012012
 

Presented by: Vanessa E. Fairbank & Dr. Amber L. Thompson
Research Leader: Dr. Andrew L. Goodwin
Published: Physical Review B

Cubic Cd(CN)2 shows the strongest known isotropic negative thermal expansion (NTE; volume contraction on heating).  Variable-temperature single-crystal X‑ray diffraction suggests there is temperature-dependent off-centering of Cd2+ ions that has the effect of increasing the cadmium coordination volume at low temperatures, providing an alternate mechanism for NTE in this material. These displacements are evident in the residual electron density and the highly-structured diffuse scattering in the experimental X-ray diffraction patterns.  Using Monte Carlo simulations, we have interpreted these patterns in terms of a basic set of “ice-rules” that establish a mapping between the dynamics of Cd(CN)2and proton ordering in cubic ice VII.

Structure of the Month – November 2012

Structure of the Month – November 2012

 

Oct 102012
 

Mr. Conor RowleyConor is spending most of his Part II year in Australia with the Cameron Kepert’s Research Group at the University of Sydney. He is working on the in situ analysis of CO2 adsorption in metal-organic frameworks. This involves a specially designed setup allowing the use of single crystal X-ray diffraction to ascertain structural information on CO2 binding in these frameworks. When not in the lab, Conor can be found learning to surf on Bondi Beach.

Apr 202012
 

The 2012 Meeting of the British Crystallographic Association was held at Warwick University.  Oxford was very well represented this year with Kirsten Christensen chairing the Programme Committee and prizes being awarded to Joe Paddison, Nick Funnell and Emma McKinley.

Other contributions from Oxford include:

Karim J. Sutton, Kirsten E. Christensen, Amber L. Thompson & Richard I. Cooper
Exploiting the Tunable Wavelength Capabilities of I19 (Poster & Oral Presentation)

Callum A. Young & Andrew L. Goodwin
An Examination of the Low Temperature Structure of Fe3O4 Using Reverse Monte Carlo Refinements (Oral Presentation)

Andrew L. Goodwin
Frameworks, Flexibility and Frustration (Oral Presentation)

Kirsten E. Christensen, Amber L. Thompson & Arwen R Pearson
Discussion Forum:  From Small Molecules to Proteins:  Bridging the Gap

Emma J. McKinley, Kirsten E. Christensen & Amber L. Thompson
Investigation of the Transient Modulated Phase of Barluenga’s Reagent (Poster)

Andrew B. Cairns, Amber L. Thompson, Andrew L, Goodwin, Matthew G. Tucker & Julien Haines
Anomalous Compression of Cyanide Frameworks:  Mechanisms for Extreme Negative Response (Poster)

Callum A. Young, Edward Dixon, Michael A. Hayward & Andrew L. Goodwin
Apical Oxygen Bonding in YBCO – A Reverse Monte Carlo Approach (Poster)

Ines E. Collings, Andrew B. Cairns, Amber L. Thompson, Andrew L, Goodwin, Philip Pattison, Julien Haines, Matthew G. Tucker, Julia E. Parker & Chiu C. Tang
Transferable Mechanics in Molecular Framework Materials (Poster)

Joseph A. M. Paddison, Andrew L. Goodwin, Ross Stewart, Pascal Manuel, Matthias J. Gutmann, David A. Keen, Matthew G. Tucker, Andrew Wildes & Brian Rainford
Frustration and Magnetic Diffuse Scattering in β-Mn0.8Co0.2 and MnO:  A Reverse Monte Carlo Study (Poster)

Matthew Cliffe & Andrew L. Goodwin
Disorder and Defects in Zirconium MOFs (Poster)

Nicholas P. Funnell, Martin T. Dove Andrew L. Goodwin Simon Parsons & Matthew G. Tucker
How Molecules Prepare to Undergo a Transition:  The Onset of Disorder in Solid Cyclohexane (Poster).

 

Karim speaks to the Young Crystallographers

Karim speaks to the Young Crystallographers

 

Emma, Richard and Ines go to the conference dinner

Emma, Richard and Ines go to the conference dinner

Ines and Emma

Ines and Emma

This time Karim brought his Dad...

This time Karim brought his Dad…

Callum and Emma at Dinner

Callum and Emma at Dinner

Kirsten presents Nick with his prize

Kirsten presents Nick with his prize

Emma receives her prize

Emma receives her prize

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Contemplating Fourier Transforms...

Contemplating Fourier Transforms…

Sep 012011
 

Presented by:  Andrew B. Cairns & Dr. Amber L. Thompson
Research Leader:  Dr. Andrew L. Goodwin
Published:  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

Structure of the Month – September 2011

Jul 282011
 

Picture of Shahzad SharifSharif is a Research Officer in the Materials Chemistry Laboratory at the GC University, Lahore. He is doing a Ph.D. in Lanthanide Coordination Polymers under the supervision of Prof. Dr Islam Ullah Khan, studying their Magnetic, Luminescent and MOF behaviour. Sharif is visiting Chem. Cryst. for six months under an IRSIP (HEC) scholarship to learn more about Crystallography and Materials Chemistry.