Research at XRD1

XRD1 and its Users

The XRD1 beamline was among the first to become operational at Elettra and has been recently upgraded after more than ten years of function. Proposals requesting beamtime at XRD1 are submitted to the Elettra Proposal Review Panel for evaluation from heterogeneous group of researchers affiliated with national and international research centers and universities. The beamline is also actively involved in collaborations with industrial partners.
The beamline offers a high degree of automation and repetitive measurements can be easily customized via a user-friendly scripting system. An automatic sample changer with a capability of 50 samples is available both for cryogenic (single crystal, small and macromolecules) and non-cryogenic (powders in capillary) samples, based on SPINE standard. The beamline offers, in parallel to diffraction, fluorescence and some spectral characterization of the specimen.
Users submitting a proposal for the first time are warmly invited to browse our publications, in order develop a clear view on the typical applications of our setup and its capabilities.

Research Fields

The beamline exploits the higher part of the spectrum (above 17 keV) for molecular structure resolution of small natural or synthetic molecules, supramolecular and self-assembly, metal organic framework systems. The available k goniometer suits these measurements allowing the sample proper (re)orientation, critical for low-symmetry specimens.
The mid part of the spectrum (8-17 keV) is widely used to tackle matter phase transitions in function of thermodynamic variables (e.g. temperature), photo-excitation, or presence of specific molecules (gas or humidity). Drug polymorphism, fibers, nanoparticles, technological materials and cultural heritage measurements are usually performed in this energy range. In these cases the large area, fast technology of the single photon counting Pilatus detector opens to time evolution of the systems as well as the presence of preferred orientations in the specimen micro-structure.
The lower energy part of the spectrum (below 10 keV) is used for grazing incidence diffraction experiments, exploiting in particular  the availability of a k-goniometer allowing a rotation of the sample to provide all diffraction signals both in plane and out of plane in case of preferred orientation or fully ordered systems.
This part of the spectrum is also used for macromolecular crystallography, where the enhancement of the anomalous signal of several light atoms of relevant biological importance (e.g. Ca, Cl, Mg, K) give the opportunity to not mistake their signals with water as well as to exploit them for phasing (e.g. S, P).
Selected examples of XRD1 applications can be found in our Highlights section.

Browse our Publications

Read our Highlights

Protein Crystallography

Small Molecules

Protein crystallography is one of the most powerful techniques for the determination of 3D structure at atomic level of proteins and large cell macromolecules. The Si 111 monochromator allows to select the energy in the range 4 to 21 keV, in MAD experiments it is necessary to perform fine scans in wavelength to determine the absorption edge of a specific element

The small molecules studies take advantage from the high intensity of the x-ray beam and from its natural collimation.

Powder Diffraction

Holography

Powder diffraction is an analytical tool for both qualitative and quantitative analysis of crystalline materials. It is widely used for polycrystalline compound. Synchrotron sources provide powerful tools to this technique that take advantage by intense and high collimated x-ray beams.

In the internal source holography, fluorescence from the atoms inside the sample is excited, and the emitted spherical wave, approaching the far-field detector directly, forms the holographic reference wave. In other direction it is scattered by neighbouring atoms, thus giving the holographic object wave.

MOFs

Grazing Incidence

Metal–organic frameworks (MOFs) are a class of compounds consisting of metal ions or clusters coordinated to organic ligands to form one-, two-, or three-dimensional structures. They are often porous and have potential application as energy storage, gas and carbon capture materials
supramolecular chemistry

Grazing incidence X-ray, typically from a crystalline structure, uses small incident angles for the incoming X-ray beam, so that diffraction can be made surface sensitive. It is used to study surfaces and layers because wave penetration is limited.