Rubidium dicalcium triniobate(V), RbCa(2)Nb(3)O(10), has been synthesized by solid-state reaction and its crystal structure refined from X-ray powder diffraction data using Rietveld analysis. The compound is a three-layer perovskite Dion-Jacobson phase with the perovskite-like slabs derived by termination of the three-dimensional CaNbO(3) perovskite structure along the ab plane. The rubidium io...

Evolutionary algorithms are finding increasing use in the study of a wide range of different types of diffraction data. In this chapter, we review recent applications of evolutionary algorithms to study a variety of structural problems. Examples range from the study of disordered materials by analysis of diffuse scattering data to molecular replacement techniques in biological crystallography. ...

The Research Associateship program of the Joint Committee on Powder Diffraction-International Centre for Diffraction Data (JCPDS-ICDD, now known as the ICDD) at NBS/NIST was a long standing (over 35 years) successful industry-government cooperation. The main mission of the Associateship was to publish high quality x-ray reference patterns to be included in the Powder Diffraction File (PDF). The...

This work presents a structural investigation of La2-xNdxCe2O7 (x = 0.0, 0.5, 1.0, 1.5, 2.0) using X-ray powder diffraction and total scattering neutron powder diffraction, analysed using Rietveld and the reverse Monte Carlo method (RMC). Ab initio molecular dynamics (MD) modelling is also performed for further investigations of the local order. The main intensities in the neutron diffraction d...

This paper introduces a two-dimensional extension of the well established Rietveld refinement method for modeling neutron time-of-flight powder diffraction data. The novel approach takes into account the variation of two parameters, diffraction angle 2θ and wavelength λ, to optimally adapt to the varying resolution function in diffraction experiments. By doing so, the refinement against angular...

This paper shows that pair-distribution function (PDF) analyses can be carried out on organic and organometallic compounds from powder electron diffraction data. Different experimental setups are demonstrated, including selected area electron diffraction and nanodiffraction in transmission electron microscopy or nanodiffraction in scanning transmission electron microscopy modes. The methods wer...

objective(s): hardystonite (ht) has been successfully prepared by a modified sol-gel method. we hypothesized thatnano-sized (ht) would mimic more efficiently the nanocrystal structure and function of natural bone apatite, owing to the higher surface area, compare to conventional micron-size (ht).materials and methods: the hardystonite nanopowder was prepared via a modified sol-gel method.optimi...

znfe2o4 mixed spinel ferrite nanoparticles obtained through a citrate-nitrate combustion method. ignited products calcined at different temperatures in 600-900ºc range and effect of calcination treatment temperature investigated. final products characterized by x-ray diffraction (xrd), fourier-transform infrared spectroscopy (ftir), and field emission scanning electron microscopy (fesem). the a...

The Powder Diffraction file has been the primary reference for Powder Diffraction Data for more than half a century. The file is a collection of about 65 000 reduced powder patterns stored as sets of d/I data along with the appropriate crystallographic, physical and experimental information. This paper reviews the development and growth of the PDF and discusses the role of the ICDD in the maint...

Conventional Fourier analysis is one of the most commonly used methods for localization of missing atoms in crystal structures from powder diffraction data. A “perfect” Fourier map would require a complete set of structure factors up to a resolution of at least sin/ = 5.0 Å. In the case of powder diffraction, accessible information is limited, as compared to single crystal diffraction, mainl...