Dec 202009
A picture of Seizure


A dreary, grey, condemned, 1960s low-rise council flat is an unusual place to find one of the most beautiful pieces of crystallographic art in the UK.  “Seizure” was constructed by transforming the flat into a watertight tank, into which 70,000 litres of hot copper sulphate solution was poured.  After three weeks of patient waiting, and cooling, the mother liquor was removed to reveal a spellbinding, blue, crystal garden. Fortunate visitors to this spectacular exhibit were entranced to behold a magical kingdom of exquisite azure crystals – everyday objects such as light fittings and baths transformed into coruscations of brilliance…



Nov 182009

Acta Cryst. (2009), C65, o635-o638.    [ doi:10.1107/S0108270109046952 ]

The unusual methylene aziridine 6-tert-butyl-3-oxa-2-thia-1-azabicyclo[5.1.0]oct-6-ene 2,2-dioxide, C9H15NO3S, was found to crystallize with two molecules in the asymmetric unit. The structure was solved in both the approximately orthogonal and the oblique settings of space group No. 14, viz. P21/n and P21/c, respectively. A comparison of these results clearly displayed an increase in the correlation between coordinates in the ac plane for the oblique cell. The increase in the corresponding covariances makes a significant contribution to the standard uncertainties of derived parameters, e.g. bond lengths. Since there is yet no CIF definition for the full variance-covariance matrix, there are clear advantages to reporting the structure in the nonstandard space-group setting.

Publisher’s copy: IUCr

Oct 302009

Inorg. Chim. Acta  (2010), 363(6), 1140-1149.    [ doi:10.1016/j.ica.2009.10.020 ]

Four 2-acetylpyridine 4N-alkyl thiosemicarbazones, and their Ga(III) and In(III) complexes have been prepared and characterised by fluorescence, UV–Vis, IR, 1H and 13C NMR spectroscopy, mass spectrometry and X-ray crystallographic analysis. Comparison of the crystal structures gave an insight into the nature of the complexes formed, demonstrating a preference for [ML2]+ type complexes with gallium and [MLX3] species with indium. Stability studies on two candidates indicated that complex [InL3Cl2MeOH] was stable to chemical degradation for prolonged periods in human serum, giving this complex potential for further biological evaluation.

Electronic reprints

  • Oxford University Research Archive [direct pdf]

Publisher’s copy


Thiosemicarbazone overlay

Overlay of two thiosemicarbazone ligands showing two different conformations.

Oct 222009

Acta Cryst. (2009), E65, o2904-o2905.    [ doi:10.1107/S1600536809043827 ]

X-ray crystallographic analysis of the title hydrobromide salt, C10H20N+Br-, of (1R,2S,3R,5R,8aR)-3-hydroxymethyl-5- methyloctahydroindolizine-1,2-diol defines the absolute and relative stereochemistry at the five chiral centres in steviamine, a new class of polyhydroxylated indolizidine alkaloid isolated from Stevia rebaudiana (Asteraceae) leaves.

Electronic reprint:

Publisher’s copy:

Oct 072009

The Nobel prize for chemistry has been jointly awarded to Venkatraman Ramakrishnan (MRC Cambridge), Thomas Steitz (Yale) and Ada Yonath (Weizmann Institute, Israel) for their work determining the structure of ribosomes.  The ribosome is an important component of cells that assembles proteins from amino acids.  It is often referred to as “the protein factory”.  This is the second Nobel prize to be awarded for work on ribosomes as Albert Claude, Christian de Duve and George Emil Palade were awarded the Nobel Prize for Medicine, in 1974 for their discovery.


  • Announcement of the 2011 Nobel Prize in Chemistry [video]
  • BBC News Online [Report]


Picture of the structure and shape of the E.coli 70S ribosome.

Structure and shape of the E.coli 70S ribosome.


Aug 212009

The 25th European Crystallographic Meeting was held in the Harbiye Museum and Cultural Centre in the beautiful city of Istanbul.  It was a very eventful week, and contributions to the conference made by Chem. Cryst. include:

N. David Brown, James Haestier, Mustapha Sadki, Amber L. Thompson & David J. Watkin
A Further Improved Structure Matching Algorithm (Poster)

James Haestier
Handling of Cell Errors and their Effect on Derived Parameters (Poster)

Mustapha Sadki
New Modelling for Disordered Atoms in Free-form Based Hybrid Refinement and Visual Representation

Mustapha Sadki
The Application of Novel Modelling and Refinement Strategies to Crystallography

Amber L. Thompson & David J. Watkin
Absolute Configuration Determination – Is there More Information in the Data? (Poster)

David J. Watkin, Richard I. Cooper & Amber L. Thompson
CRYSTALS:  Refinement and Validation Tools (Poster)

David Watkin
The Future of Small Molecule Software (Session Chair)

Aug 212009

Dr. Jeppe ChristensenJeppe’s specialist areas are crystallographic instrumentation, experiment design, weak diffraction, twinning and modulation. He is also very knowledgeable about software and the theoretical basis of crystallography. Formerly beamline manager at the Swedish synchrotron facility MAX IV Laboratory, where he operated the small molecule and powder diffraction beamline, Jeppe is currently Research Officer in the Dynamical Structural Science group at the Research Complex at Harwell where he is involved in the development of time resolved crystallography.

Aug 012009

J. Appl. Cryst. (2009), 42, 798-809.    [ doi:10.1107/S0021889809024376 ]

A new method is presented for handling errors on crystallographic data. In single-crystal diffraction experiments, two variance-covariance matrices are present, one for the cell parameters and the second for the refined parameters (atomic coordinates and anisotropic displacement parameters). These two matrices can be combined so that errors on derived parameters, such as bond distances, bond angles and TLS tensors, may be calculated more simply. The new method works for all space groups but there are limitations on its application to triclinic space groups. The method allows errors to be transformed between space groups.

Publisher copy: IUCr

May 072009

Tet. Asym. (2009), 20, 712-717.    [ doi:10.1016/j.tetasy.2009.02.025 ]

Advances in hardware and software have made X-ray crystallography even more attractive as the first-option method for structure analysis. For most organic materials containing up to 100 non-hydrogen atoms, getting from the initial visual examination of the sample to producing publication-ready tables and pictures should usually be achievable in a single morning. Improvements in hardware have also increased reliability of the determination of absolute configuration. A recently published new algorithm may extend the range of applicability of the method.

Le Coup de Roi

Le Coup de Roi: making two chiral pieces from an achiral whole