BL17B

Home BeamlinesSSRFBeamline MapsBL17BBeamline introduction
Scientific Scope
More
The BL17B High-Throughput Crystallography Beamline boasts a broad energy tuning range, combining the characteristics of high flux, high brightness, high energy resolution, and continuous energy tunability of synchrotron radiation X-Ray. Its Single-Crystal  X-ray diffraction (SCXRD) method is not only suitable for large molecular protein crystal structure analysis but also supports small molecule single-crystal structure investigations, such as Materials like Metal-Organic Frameworks (MOFs), Covalent Organic Frameworks (COFs). This beamline also enables various methodological studies, including Powder X-ray Diffraction (PXRD), Grazing Incidence Wide Angle X-ray Scattering (GIWAXS), and X-ray Absorption Fine Structure Spectroscopy (XAFS). These methodologies enable the study of structures from crystalline to amorphous states, making it applicable across various disciplines, including biology, medicine, environmental science, and energy materials.
Beamline Layout
More
 
Specifications
More
 Specifications  BL17B
 Energy range  5~23 keV
 Energy resolution (ΔE/E)  ≤ 3×10-4
 Flux at sample  ≥3×1011 phs/s (12keV@300mA）
 Focused beam size  ≤150×180 μm2
 Beam divergenc  ≤1.5×0.2mrad2 (H×V)
Endstations
More
The BL17B beamline has 3 sub-experimental end-stations: Single Crystal/ Powder X-ray Diffraction (SCXRD/PXRD), Grazing Incidence Wide Angle X-ray Scattering (GIWAXS), and X-ray Absorption Fine Structure Spectroscopy (XAFS). By interchanging equipment along the optical path, we can change three distinct experimental modes individually.
BL17B experimental endstation layout diagram
BL17B experimental endstation
End-station 1 -- SCXRD/PXRD
1)SCXRD (Single Crystal X-ray Diffraction)
Experimental Method-- Single-crystal diffraction techniques can characterizing the three-dimensional atomic structure of crystals, are widely employed in the structural analysis of large molecules such as proteins and peptides, as well as in small molecule crystals like MOFs, COFs, and supramolecular assemblies. 
Data Collection-- The experiment utilizes the MD2 single-crystal diffractometer and a Pilatus 2M pixel-array detector to collect diffraction patterns at continuously rotating angles. Single crystal is supported by the loop of the SPINE-type magnetic sample holders, and then mounted on the goniometer head. It is recommended that the single crystal size is generally greater than 15 microns. A maximum diffraction resolution of 0.77 Angstroms can be achieved by adjusting the incident light energy and the distance between the detector and sample. The MXcube control system software is utilized.
Data Analysis-- Single-crystal diffraction raw data requires processing via reduction software to yield an HKL file that provides intensity data for the diffraction points, which is utilized for the final atomic structure determination. The beamline is equipped with automated data reduction capabilities, making the processed data available for user use. Additionally, manual data reduction software options are offered, such as HKL3000 and APEX4.
2)PXRD (Powder X-ray Diffraction) 
Experimental Method-- PXRD is suitable for phase identification and analysis of crystal structures for non-single-crystalline samples, such as powders, blocks, and thin films. PXRD experiments utilize the same equipment as SCXRD experiments, but only needs to collect single diffraction pattern. This technique boasts the advantage of sub-second time resolution, and when combined with temperature control devices at the sample location, it enables in-situ variable-temperature experiments, allowing the study of dynamic changes in crystal structure with temperature and time. 
PXRD experiment
Data Collection-- Powder is encapsulated using a glass capillary or Kapton film, and secured at the rear end of a magnetic sample holder, which is then placed on the goniometer head of the diffractometer. By adjusting the incident light wavelength and detector distance, the 2 theta angular range can be modified. For instance, with 18 keV (0.688 Å) energy, a 110 mm detector distance, the angular range is 0.04° < 2θ < 60.57° (equivalent to 0.1° < 2θ < ~177° with a standard laboratory copper target source at 1.54 Å). Under the same experimental conditions, a standard sample (LaB6) is collected for calibrating the detector distance and beam center (i.e., 0°). An empty sample is also collected to subtract the background. 
Data Analysis-- Radial integration around the center of the 2D diffraction ring, originating from the optical center, can converts the two-dimensional diffraction image into a common one-dimensional diffraction spectrum. Data processing can be performed using software such as Fid2d, Dioptas, or pyFAI.
 
End-station 2 -- Grazing Incidence Wide Angle X-ray Scattering (GIWAXS)
1)Experimental Method
The GIWAXS technique can characterizes crystal structures, crystal orientations, and lattice constants at interfaces across various depths, widely employed in the structural characterization and dynamic behavior monitoring of thin films, coatings, and catalyst surfaces. In a GIWAXS experiment, X-rays incident at a shallow angle onto the sample surface, and two-dimensional area detectors collect the scattered X-ray signals along the reflection direction. By integrating remote controlled sample loading systems, temperature-controlled spin coaters, vacuum evaporators, and atmosphere chambers onto the GIWAXS platform, it enables offline testing, in situ heating, in situ spinning, in situ atmospheric conditions, and even experiments under multiple in situ scenarios.
GIWAXS experiment
2)Data Collection and Analysis
a)Sample test range (10 keV as an example):
Off-line testing: q (0.23~3.7 Å)
In situ device testing: q (0.12~2.7 Å)
b)test procedure
Recommended sample dimensions are 15×15 mm or 20×20 mm.
Before collecting data from each sample, it is necessary to ensure the surface of the specimen under an incident angle of 0° using a semi-transmission method. Then adding an defined grazing incidence angles, and proceed to data acquisition procedure.
Under identical experimental conditions with the same sample position and incident light energy, a standard sample (LaB6) is measured to calibrate the detector distance and beam center. 
An empty sample is also collected to subtract background noise. 
Data processing can be performed using software such as Fid2d, GIWAXS-Tools, Dioptas, or pyFAI.
 
End-station 3 -- XAFS (X-ray Absorption Fine Structure Spectroscopy) 
1)Experimental Method
The XAFS technique can characterize short-range ordered atomic structures, extracting local coordination information around the absorbing atom. The Near Edge Structure (XANES) can characterize oxidation state, symmetry, and orbital occupancy. The Extended XAFS (EXAFS) can characterize the types of neighboring atoms, coordination distances, coordination numbers, and disorder. XAFS boasts the advantages of elemental selectivity, independence from crystal structure, and no restrictions on sample morphology, making it widely applied in energy, materials, nanotechnology, biology, geology, and environmental sciences research.
XAFS experiments platform employ three ionization chamber system to simultaneously collect transmission absorption spectra for both the sample and reference sample. An energy reference will be embedded in each data by the reference sample data, enabling comparison between data collected under different machine conditions. Fluorescence data from the sample are synchronously collected with transmission data, allowing for quick one-button switching between two types of fluorescence detectors - Total Fluorescence Yield (Lytle) and Partial Fluorescence Yield (SDD) - to cover testing for samples with varying concentrations.
XAFS spectrum collected by BL17B
The beamline uses a three-ionization chamber system to simultaneously collect transmission absorption spectra of samples and standards. The fluorescence data of the samples and transmission data are collected synchronously. The system allows for quick switching between two types of fluorescence detectors—total fluorescence yield Lytle and partial fluorescence yield SDD—at the push of a button, covering tests of both high and low concentration samples.
(a) Schematic and (b) physical layout of the XAFS experimental station
2)Data Collection and Analysis
experimental range: Energy range from 5 to 23 keV, covering the K-edge of Ti to Ru and the L3-edge of Cs to Lu. (5-6 keV is temporarily unavailable).
XAFS Specification： Parameters
Energy range： 5-23 keV, 7-21 keV (recommended)
Energy resolution (ΔE/E)： < 2×10-4 @10 keV
Flux at sample： 2.2×1011 phs/s @10 keV
Focused beam size： <1.5 × 0.6 mm2 (H×V)
Elements feasible for XAFS experiment
•High-throughput and Automated Testing: A 25-position high-capacity sample wheel is used for remote sample loading, enabling automated sample screening for the same element and simultaneous collection of absorption spectra in transmission mode and Lytle fluorescence mode. For sample preparation, it is recommended to prioritize uniform pellet pressing, with a total absorption length of approximately 2 and a diameter of 10-15 mm. To improve experimental efficiency, samples should be prepared in advance at the user's location, as the beamline does not provide onsite sample preparation facilities.
•Compatibility: Supports in-situ sample cells, grazing incidence sample stages, and manual loading of conventional sample holders.
•Extremely Low Test Concentration Limit: For CuPc samples diluted with LiF, EXAFS data can be measured down to 0.04 wt%, and XANES data can be measured down to 0.01 wt%.
•Data Format: XDI data format. The header includes beamline information and experimental details. The experimental data includes raw data as well as converted transmission data, fluorescence data, and standard sample data.