| Scattering |
 |
|
Hard x rays have wavelengths comparable to the distance between atoms. Essentially everything we know about the atomic structure of materials is based on results from x-ray and neutron diffraction. From advanced ceramics to catalysts, from semiconductor technology to the frontiers of medicine, and from new magnetic materials and devices to framework compounds used to sequester radioactive waste, crystallography using hard x-ray diffraction techniques at synchrotron radiation facilities plays a crucial role in our ability to understand and control the world in which we live. The scattering of x rays from protein crystals is the most powerful method of determining the three-dimensional structure of large biological molecules (macromolecules). Because macromolecules are large and flexible, their crystals tend to be small, imperfect, and weakly diffracting. In many cases, the intensity, small beam size, and collimation of a synchrotron beam is vital for successful results. Soft x-ray scattering techniques employ the excitation of electrons in relatively shallow core energy levels (100–2000 eV) to probe the electronic structure and other properties of various kinds of matter. The sample is illuminated with monochromatic soft x rays and the scattered photons are detected over a small angular range. In the elastic scattering mode one measures the speckle diffraction pattern. In the inelastic mode the scattered photons are passed through a spectrometer and analyzed. Selected Scattering Highlights
Dynein Motor Domain Shows Ring-Shaped Motor, Buttress Lensless X-Ray Imaging in Reflection Mineral Deformation at Earth's Core–Mantle Boundary Inhibiting Individual Notch Receptors Improves Treatment Two Novel Ultra-Incompressible Materials A New Light on Disordered Ensembles Heterogeneous Morphology Found in Organic Solar Cells Giant Protease TPP II’s Structure, Mechanism Uncovered Topoisomerase II Structure Suggests Novel DNA Cleavage Mechanism The Surprising Appearance of Nanotubular Fullerene D5h(1)-C90 Structure of All-Polymer Solar Cells Impedes Efficiency Mechanical Behavior of Indium Nanostructures Lensless Imaging of Whole Biological Cells with Soft X-Rays A New Route to Nano Self-Assembly Rotary Firing in Ring-Shaped Protein Explains Unidirectionality Structures of the Ribosome in Intermediate States of Ratcheting Proton Channel Orientation in Block-Copolymer Electrolyte Membranes Hybrid Rotaxanes: Interlocked Structures for Quantum Computing? P-Glycoprotein Structure and Chemotherapy Resistance Molecular-Frame Angular Distributions of Resonant Auger Electrons |
