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Didcot, United Kingdom

Diamond Light Source is the UK's national synchrotron science facility located in Oxfordshire, United Kingdom. Its purpose is to produce intense beams of light whose special characteristics are useful in many areas of scientific research. In particular it can be used to investigate the structure and properties of a wide range of materials from proteins , and engineering components to conservation of archeological artifacts . The facility's name is abbreviated to Diamond throughout this article. Wikipedia.

Nave C.,Diamond Light Source
Journal of Synchrotron Radiation | Year: 2014

An analysis is given of the effect of different beam and detector parameters on the sharpness of recorded diffraction features for macromolecular crystals of different quality. The crystal quality parameters include crystal strain, crystal or mosaic block size and mosaic block misorientation. Calculations are given for instrument parameters such as angular resolution of the detector, beam divergence and wavelength bandpass to be matched to the intrinsic diffraction properties from these crystals with the aim of obtaining the best possible data out of each crystal. Examples are given using typical crystal imperfections obtained from the literature for both room-temperature and cryo-cooled crystals. Possible implications for the choice of X-ray source, beamline design, detector specifications, instrument set-up and data processing are discussed, together with the limitations of the approach. © 2014 International Union of Crystallography. Source

Christensen K.E.,Diamond Light Source
Crystallography Reviews | Year: 2010

For zeolite-type frameworks the focus has for a long time been put on producing new structures that can give optimized properties for a variety of different purposes. Many new structures have been produced on a trial and error basis. Open-framework germanates have played the role of forming many new structures as it is easier to form certain building units within the germanate system. It is time to start comparing synthesis mechanisms and building units to determine how we can control the synthesis. Here we will give an overview of some of the structures found within the open-framework germanate system and demonstrate that in order for more optimized systems to be synthesized there is a clear need for the more detailed comparison of the structural systematics of existing materials. © 2010 Taylor & Francis. Source

Jephcoat A.P.,Diamond Light Source
Nature Materials | Year: 2011

Eremets and Troyan achieved room-temperature compression and also sputtered electrodes into the diamond-anvil cell that allowed the conductivity of the sample to be measured, hence going directly to the heart of the process needed to confirm metallization. The authors passivated the diamond surface with a thin layer of sputtered gold or copper, which, while maintaining high transparency for visible light, prevented pressurized hydrogen from contacting bare diamond, a notoriously ill-suited combination in this type of set-up. Eremets and Troyan extrapolate a zero-bandgap state to 260-270 GPa. As pressure increases above 200GPa, they observe a rapid decrease in Raman vibron frequency ascribed to molecular hydrogen, in stark contrast with studies at lower temperature. A pronounced hysteresis is also observed on decreasing the pressure, the molecular Raman activity returns only at around 200 GPa indicating a first order transformation, as would be expected across a melting transition. Source

Van Der Laan G.,Diamond Light Source
Physical Review Letters | Year: 2012

The sum rule for the branching ratio of dipole-excited core-valence transitions in isotropic x-ray absorption spectroscopy is extended to electric multipole transitions. The derived sum rule not only shows that the branching ratio is linearly related to the expectation value of the angular part of the spin-orbit operator in the valence states, but also shows a strong dependence on the rank of the multipole. The spin-orbit dependence vanishes in the weighted sum over the branching ratios. The effect can be an important diagnostic tool for high-energy spectroscopies. © 2012 American Physical Society. Source

Van Der Laan G.,Diamond Light Source
Journal of Physics: Conference Series | Year: 2013

Applications of x-ray magnetic circular and linear dichroism (XMCD and XMLD) are reviewed in the soft x-ray region, covering the photon energy range 0.4-2 keV, which includes important absorption edges such as the 3d transition metal L2,3 and rare earth M4,5. These techniques enable a broad range of novel and exciting studies such as on the electronic properties and magnetic ordering of novel nanostructured systems. XMCD has a sensitivity better than 0.01 monolayer (at the surface) and due to simple detection methods, such as electron yield and fluorescence yield, it has become a workhorse technique in physics and materials science. It is the only element-specific technique able to distinguish between the spin and orbital parts of the magnetic moments. The applications are vast, e.g., in x-ray holographic imaging, XMCD gives a spatial resolution of tens of nm. While many studies in the past were centered on physics, more recently new applications have emerged in areas such as chemistry, biology and earth and environmental sciences. For instance, XMCD allows the determination of the cation occupations in spinels and other ternary oxides. In scanning transmission x-ray microscopy (STXM), XMCD enables us to map biogenic magnetite redox changes resulting in a surprising degree of variation on the nanoscale. Another recent development is ferromagnetic resonance (FMR) detected by time-resolved XMCD which opens the door to element-, site- and layer-specific dynamical measurements. By exploiting the time structure of the pulsed synchrotron radiation from the storage ring the relative phase of precession in the individual magnetic layers of a multilayer stack can be determined. Source

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