Advantages of a curved image plate for rapid laboratory-based x-ray total scattering measurements: Application to pair distribution function analysis

Quick and robust PDF data acquisition using a laboratory single-crystal X-ray diffractometer for study of polynuclear lanthanide complexes in solid form and in solution

Self-assembled polynuclear lanthanide hydroxo complexes are important objects in the reticular chemistry approach to the design of various functional materials. Revealing their structure in the solid state and understanding the molecular mechanism of self-assembly in solution require a universal and reliable structural method. Pair distribution function (PDF) analysis is a powerful technique which enables structural insight for a wide range of crystalline and amorphous materials on the nanoscale, but commonly measurements are performed at synchrotron X-ray sources or on specially designed laboratory diffractometers. In the present paper, a standard Bruker D8 QUEST single-crystal X-ray diffractometer equipped with a micro-focus Mo tube and CMOS Photon III detector was adapted to measure PDF data of high quality with Q max = 16.97 Å–1 for solid and liquid samples. An improved data collection strategy and the original data reduction software FormagiX enable calibration and azimuthal full-frame integration of 2D frames, delivering reliable PDFs up to 80 Å with instrumental parameters Q damp = 0.018 Å−1 and Q broad = 0.010 Å−1. The effectiveness of the developed approach was demonstrated with reference samples and real-case studies of tetranuclear lanthanide hydroxocarboxylates in solid form and in solution.

A multipurpose laboratory diffractometer for operando powder X-ray diffraction investigations of energy materials

This paper describes the design and implementation of an in-house laboratory powder X-ray diffractometer tailored for structural investigations of energy materials. The performance characteristics of the diffractometer together with some example research applications are presented.

Laboratory X-ray diffractometers are among the most widespread instruments in research laboratories around the world and are commercially available in different configurations and setups from various manufacturers. Advances in detector technology and X-ray sources push the data quality of in-house diffractometers and enable the collection of time-resolved scattering data during operando experiments. Here, the design and installation of a custom-built multipurpose laboratory diffractometer for the crystallographic characterization of battery materials are reported. The instrument is based on a Huber six-circle diffractometer equipped with a molybdenum microfocus rotating anode with 2D collimated parallel-beam X-ray optics and an optional two-bounce crystal monochromator. Scattered X-rays are detected with a hybrid single-photon-counting area detector (PILATUS 300K-W). An overview of the different diffraction setups together with the main features of the beam characteristics is given. Example case studies illustrate the flexibility of the research instrument for time-resolved operando powder X-ray diffraction experiments as well as the possibility to collect higher-resolution data suitable for diffraction line-profile analysis.

Symmetry-adapted pair distribution function analysis (SAPA): a novel approach to evaluating lattice dynamics and local distortions from total scattering data

A novel symmetry-adapted pair distribution function analysis (SAPA) method for extracting information on local distortions from pair distribution function data is introduced. The implementation of SAPA is demonstrated in the TOPAS-Academic software using the freely available online software ISODISTORT, and scripts for converting the output from ISODISTORT to a SAPA input file for TOPAS are provided. Finally, two examples are provided to show how SAPA can evaluate the nature of both dynamic distortions in ScF3 and the distortions which act as an order parameter for the phase transitions in BaTiO3.