V. A. Shishkov

The belok station for protein crystallography on the synchrotron radiation beam from the bending magnet in the Sibir-2 storage ring

Design modifications made in the initial project of the Belok station in the Sibir-2 storage ring and the alignment and calibration methods are considered. The main operating parameters of the station are reported. Protein single crystals in a capillary at T = 293 K and without a capillary at T = 95 K, powders (angular resolution Δ2ϑ = 0.04°), and nanocrystalline Na and Cl2 precipitates (sizes, shape, and orientation) in electron-irradiated NaCl crystals have been investigated. The problem of focusing of a short-wavelength synchrotron radiation beam with sagittal bending of the second crystal in the double-crystal monochromator at a limited source-to-sample distance is solved in the Belok project.

Upgraded X-ray topography and microtomography beamline at the Kurchatov synchrotron radiation source

An upgraded X-ray Topography and Microtomography (XRT-MT) station is described, the parameters of the optical schemes and detectors are given, and the experimental possibilities of the station are analyzed. Examples of tomographic reconstructions are reported which demonstrate spatial resolutions of 2.5 and 10 μm at fields of view of 2.5 and 10 mm, respectively.

X-ray parabolic collimator with depth-graded multilayer mirror

A very reliable and easily adjustable x-ray parabolic collimator with uniform intensity distribution in its output cross section is designed using the technology of depth-graded multilayer mirrors. The W/C multilayer mirror structure was specially designed so as to compensate for the decrease in output intensity at lower grazing angles. The advantages of depth-graded multilayer mirrors with respect to laterally graded ones are inexpensive and versatile technology, the absence of any need of precise axial adjustment along the parabolic profile, and the possibility of creating any desired reflection curve shape. With a focal length of 1015 mm and a source projection of 0.1 mm, the total angular divergence of the output beam was measured to be 25 angular seconds at Cu Kα radiation, i.e., only 5 arcsec larger than the theoretical limit. The total output flux at both the Cu Kα1 and Cu Kα2 lines is a factor of 50 larger than that delivered by a conventional Si(111) monochromator.

Modular goniometer set for high-resolution X-ray diffraction experiments using synchrotron radiation

Abstract A set of goniometer modules is described that allows easy assembling of the necessary optical layouts for experiments using synchrotron radiation. The technical parameters of the goniometers are given, and examples of setups assembled from the set elements are presented. Software drivers for the goniometers are described. Experimental results obtained with the use of an instrument based on the set are reported.

Thermal strains in focusing channels of the stations for X-ray diffraction analysis in the Sibir-2 storage ring

The thermal load caused by the absorption of synchrotron radiation in X-ray optical elements of the Belok and RSA stations leads to optics elements heating and induces strains upon simultaneous cooling. The heating of the cooled first crystal in the double-crystal monochromator causes its bending and increases the reflected beam divergence, which, in turn, results in the monochromatic beam intensity loss [1]. Numerical simulation makes it possible to more accurately determine the strains, choose the optimal monochromator design, estimate the vertical sizes of the focal spot and wavelength resolution in the focusing channel, correctly design the system for cooling the mirror at the channel input, and choose a design providing the minimum temperature of the beam-limiting slit knives.

New scientific equipment for protein crystallization in microgravity, BELKA, and its approbation on the Bion-M No. 1 spacecraft

A space experiment on the crystallization of lisozyme and glucose isomerase proteins in UK-1 and UK-2 crystallizers on the scientific equipment BELKA on the Bion-M no. 1 spacecraft was performed in April–May 2013. A ground-based experiment was carried out simultaneously at the Institute of Crystallography of the Russian Academy of Sciences (IC RAS). Transparent crystals were obtained in both cases. The lisozyme crystals grown in microgravity are larger than their terrestrial analogs. An optical study of glucose isomerase crystals grown in space has shown that the coalescence of equally oriented crystallites leads to the formation of quasi-single-crystal blocks. An X-ray diffraction experiment on lisozyme crystals has revealed the resolutions for crystals obtained under terrestrial conditions and in space to be 1.74 and 1.58 Å, respectively.

Station for X-ray structural analysis of materials and single crystals (including nanocrystals) on a synchrotron radiation beam from the wiggler at the Siberia-2 storage ring

The design of the station for structural analysis of polycrystalline materials and single crystals (including nanoobjects and macromolecular crystals) on a synchrotron radiation beam from the superconducting wiggler of the Siberia-2 storage ring is described. The wiggler is constructed at the Budker Institute of Nuclear Physics of the Siberian Division of the Russian Academy of Sciences. The X-ray optical scheme of the station involves a (1, −1) double-crystal monochromator with a fixed position of the monochromatic beam and a sagittal bending of the second crystal, segmented mirrors bent by piezoelectric motors, and a (2θ, ω, φ) three-circle goniometer with a fixed tilt angle. Almost all devices of the station are designed and fabricated at the Shubnikov Institute of Crystallography of the Russian Academy of Sciences. The Bruker APEX11 two-dimensional CCD detector will serve as a detector in the station.

Crystal monochromator with a large curvature of the sagittal bending

A new crystal monochromator is designed and tested. The crystal monochromator allows for the use of a large curvature of the sagittal bending and makes it possible to focus synchrotron radiation at a short wavelength and a limited distance from the synchrotron radiation source to the sample.

Beam focusing on stations with a Sibir’-2 synchrotron source for single-crystal studies of atomic structures

A scheme for obtaining a stationary monochromatic beam that can be focused in the horizontal and the vertical planes and rapidly tuned to a desirable wavelength with the aid of a bending magnet on a Sibir’-2 synchrotron source has been designed. The channel parameters and the size and profile of a sagittally bent single crystal of the double-crystal monochromator were chosen with the use of numerical simulation.

X-ray instrumentation for SR beamlines

Abstract The main possibilities and parameters of experimental X-ray stations are presented: “Protein crystallography”, “X-ray structure analysis”, “High-precision X-ray optics”, “X-ray crystallography and material science”, “X-ray topography”, “Photoelectron X-ray standing wave” that are being installed at Kurchatov SR source by A.V. Shubnikov Institute of Crystallography.