Developments in X-ray analysis hardware and software have combined to dramatically improve the throughput, speed, and accuracy of formulation analyses. We will focus on a complimentary development, the growth and application of a comprehensive database based on the Powder Diffraction File™ (PDF®). The PDF is an edited and standardized combination of several crystallographic databases with ∼497 000 published entries. The comprehensive nature of this database, combined with phase identification and digital pattern simulations, was used to identify complex formulations with crystalline and noncrystalline ingredients. We will show how these parallel developments enhance the ability to correctly identify complex formularies.

Two polymorphs of Holmium molybdate, known as β'-phase and γ-phase, were prepared by solid state reaction with different thermal treatments. These polycrystalline samples have been studied for the first time by X-ray thermodiffractometry from room temperature up to 1300 K. We found that the initial β'-phase undergoes a transition to a β-phase and then to a γ-phase. The γ (hydrated)-phase, turns to the γ (dehydrated)-phase and then to the β-phase. Each sequence involves a reversible and an irreversible phase transition for Ho2(MoO4)3. Both polymorphs have remarkable physical properties like nonlinear optics, ferroelectricity and negative thermal expansion. We have calculated the linear expansion coefficients of both phases. We have obtained a positive coefficient for the β'-phase and a negative one for the γ-phase. Moreover, we have made a comparison of the obtained coefficients with previous results for other rare earth molybdates.

Shot peening was conducted on [100]- and [111]-oriented monocrystalline nickel-based superalloy samples to study the effect of crystal orientation on the distributions of the residual stress and evolution of microstructures in the deformation layers on the sample surfaces as a function of the coverage up to 400%. The XRD results show that the orientation randomizations and the values of compressive residual stress in the [111]-oriented samples are relatively higher than those in the [001]-oriented samples. Moreover, the residual-stress distribution in each sample is anisotropic, and the residual stress is maximum along the 〈110〉 direction. This phenomenon can be explained by the anisotropic properties of a single-crystal alloy and mechanism of the dislocation slip in the plastic deformation layers. Line profile analysis was also used to obtain microstructural information of the samples.

A new ternary compound Gd117Fe52Ge112 has been successfully synthesized and studied by means of X-ray powder diffraction technique. Gd117Fe52Ge112 crystallizes in a cubic Tb117Fe52Ge112-type structure with space group Fm3m(#225) and lattice parameter a=28.7680(1) Å. Crystal structure of Gd117Fe52Ge112 has been successfully refined using the Rietveld method from X-ray diffraction data. The R-factors for the Rietveld refinement are Rp=0.099 and Rwp=0.128. X-ray powder diffraction data with the figure of merit F30 of 80.4(30) are also reported.

A wide range of transition metal oxide solid solutions have been prepared and characterised using powder X-ray diffraction (MnxCo1−xFe2O4, FexCo1−xFe2O4, NixCo1−xFe2O4, FeFexCr2−xO4, MnFexCr2−xO4, MnxFe1−xCr2O4, MnxFe1−xFe2O4, NixFe1−xFe2O4). Calibration curves have been obtained relating oxide composition to unit cell parameter or d spacing. From these curves it is possible to identify the composition of oxides formed on steel surfaces in varied industrial environments. Even when poor diffraction patterns are obtained and little sample is available, an estimate of composition can be made.

The crystal structures of the chiolite-related room temperature phases α-Na5M3F14 (MIII=Cr,Fe,Ga) are determined. For all of them, the space group is P21/n, Z=2; a=10.5096(3) Å, b=7.2253(2) Å, c=7.2713(2) Å, β=90.6753(7)° (M=Cr); a=10.4342(7) Å, b=7.3418(6) Å, c=7.4023(6) Å, β=90.799(5)° (M=Fe), and a=10.4052(1) Å, b=7.2251(1) Å, c=7.2689(1), β=90.6640(4)° (M=Ga). Rietveld refinements produce final RF factors 0.036, 0.033, and 0.035, and RWP factors, 0.125, 0.116, and 0.096, for MIII=Cr, Fe, and Ga, respectively. The MF6 polyhedra in the defective isolated perovskite-like layers deviate very few from perfect octahedra. Subtle octahedra tiltings lead to the symmetry decrease from the P4/mnc space group adopted by the Na5Al3F14 chiolite aristotype to the P21/n space group adopted by the title series. Facile twinning precluded till now the precise characterization of these compounds.

The laboratory implementation of grazing incidence in-plane X-ray diffraction, using an unmodified commercial diffractometer, is described. Low resolution, high intensity measurements are illustrated in the study of the in-plane lattice parameters and texture of a thin polycrystalline ZnO film on glass, the in-plane order in Cd arachidate Langmuir–Blodgett films, and the depth dependence of the lattice parameter in graded Si–Ge epilayers. Use of an asymmetrically cut Ge crystal to compress and monochromate the beam provides a high resolution setting, appropriate to measurement of the in-plane mosaic of mismatched epilayers such as GaN on sapphire.

A new X-ray powder diffraction pattern for α-Si3N4is presented and compared with the current PDF pattern. The necessity for an updated pattern is discussed.

The crystal structure of metastable Li2Si2O5, Fw = 150.05, has been refined by the Rietveld method using high resolution X-ray powder diffraction data recorded at the Daresbury Synchrotron Radiation Source on the new 8.3 diffractometer. Li2Si2O5, in keeping with many compounds of interest to the materials scientist, exhibits relatively broad diffraction peaks. It is important to establish the quality of crystal structure data that may be obtained from such materials on this new instrument. Various functions were used to model the peak shape from this instrument; a split-Pearson VII function appeared to be marginally superior to Pearson VII or Pseudo-Voigt functions. Refinement was carried out using the split-Pearson VII in the space group Pbcn (60) and terminated with a = 5.6871(6), b = 4.7846(5), c = 14.645(1) Å, V = 398.50 Å3, Z=4, Dc= 2.502 gcm−3, Rwp = 17.06, Rex = 14.48 and Χ2 = 1.39. The refined parameters are compared with those obtained from a previous single crystal X-ray determination.

High-resolution neutron powder diffraction (NPD) data were recorded on a series of cathode material LiFe1−xMnxPO4 (x = 0, 0.2, 0.5, 0.8, and 1.0) solid solutions using the HRPD machine at SINQ/PSI, Switzerland. Ab initio crystal structure solution via program FOX indicates demonstrably that the space group of LiFePO4 is Pnma with Li1+ occupying octahedral (4a) sites and Fe2+ octahedral (4c) sites, respectively, in the olivine structure. Rietveld refinement (program FullProf suite version July-2011), complementary with X-ray diffraction data, shows that Fe2+ may partially (about 2%) distribute over Li1+ sites. NPD data for LiFe1−xMnxPO4 (x = 0, 0.2, 0.5, 0.8, and 1.0) reveal that the Mn2+ replaces Fe2+ at the octahedral (4c) sites. The cell parameters a, b, and c increase linearly and the interatomic distances (in Å) of Li–O(2) and Li–O(1) increase, while the interatomic distances (in Å) of Li–O(3) decrease on the addition of Mn, respectively, partially explaining a higher potential plateau of ~4.1 eV in LiMnPO4 compared to ~3.5 eV in LiFePO4.

The National Institute of Standards and Technology (NIST) certifies a suite of Standard Reference Materials (SRMs) to be used to evaluate specific aspects of the instrument performance of both X-ray and neutron powder diffractometers. This report describes SRM 640f, the seventh generation of this powder diffraction SRM, which is designed to be used primarily for calibrating powder diffractometers with respect to line position; it also can be used for the determination of the instrument profile function. It is certified with respect to the lattice parameter and consists of approximately 7.5 g of silicon powder prepared to minimize line broadening. A NIST-built diffractometer, incorporating many advanced design features, was used to certify the lattice parameter of the Si powder. Both statistical and systematic uncertainties have been assigned to yield a certified value for the lattice parameter at 22.5 °C of a = 0.5431144 ± 0.000008 nm.

The synthesis of a new family of aluminophosphate-based molecular sieves containing pores defined by 18 tetrahedrally linked atoms has been described by Davis et al at Virginia Polytechnic Institute (VPI). This development reprsents the first reposted synthesis of a moleoular sieve with pores larger than those defined by 12 tetrahedrally linked atoms. This material has been shown to readily absorb triisopropyl benzene and exhibits a pore size distribution, determined from, its argon adsorption isotherm, which suggests the existence of molecular sieve pores larger than those found in known molecular sieves. Confirmation of a pore defined by 18 tetrahedrally linked aluminum and phosphorus atoms was accomplished by crystallographic structure determination using X-ray powder diffraction data. Single crystal methods were impossible due to an inability to synthesize crystals of suitable size. Details of the structure determination are reported in this work.

High-temperature X-ray diffractometer measurements by the Bureau showed that alpha-alumina expands anisotropically with expansion parallel to the c axis approximately 10% greater than that parallel to the a axis. Thermal-expansion characteristics of four different alumina samples were determined up to 1200°C; the results are presented in both tabular and graphical form. The combined random and systematic errors in the measurements are considered less than 3% above 500°C and approximately 2% at 1000°C. No differences in expansion were observed between the samples or between the heating and cooling cycles.

Critical evaluation of the literature showed that published values for thermal-expansion coefficients of single crystals vary over a range of 40% (relative values) and disagreement concerning whether expansion of alpha-alumina is isotropic or anisotropic. Systematic and experimental errors were found to be the principal factor for the variation in results, rather than differences in measuring techniques or in samples.

Published values for polycrystalline aggregates also varied. Two laboratories reported values 20–30% lower than those of the Bureau of Mines, but two other laboratories agree with the Bureau within 3–5% above 500°C.

X-ray diffraction observation of metal fractures provides fracture analysists with useful information on the mechanisms and mechanical conditions of fracturing. This method is called “X-ray fractography” and has been developed especially in Japan as a new engineering tool for fracture analysis.

In the present paper, X-ray fractography is applied to fracture surfaces of ductile cast iron (JIS FCD 60) which are widely used as machine parts. The fracture toughness tests were conducted at ambient and low temperatures by using compact tension (CT) specimens with blunt notches and three-point bending (TPB) specimens with fatigue pre-cracks. The line broadening of X-ray diffraction profiles was measured on and beneath fracture surfaces of fracture toughness specimens.

Methods of quantitative electron probe analysis using empirical working curves have achieved only partial success because of variations in instrument design, analysis conditions, and homogeneity of standards. These problems have been solved for X-ray fluorescence analysis, but many of the more successful empirical methods cannot be used in electron probe analysis; instead, a more theoretical approach is indicated. In electron probe analysis quantitative results can be achieved with only pure elements as standards provided (1) the analysis conditions are carefully selected, (2) the observed intensities can be corrected to obtain the primary intensity actually produced in the specimen, and (3) the relationship of the primary intensity and concentration can be calculated. While present methods of making some of the corrections required improvement and a “universal” theory for relating the primary X-ray intensities to the concentrations still does not exist, the success achieved with this approach indicates that it should be used to the fullest extent before resorting to calibration curves. Moreover, as information is accumulated, the number of cases requiring the use of calibration curves should diminish, so that eventually it may be possible to perform quantitative analysis in any system with only pure elements as standards,

Presented here is a report on the development of practical techniques for laboratory spectroscopy in the 5 to 150 A wavelength region as may be applied, for example, to light element and surface state analysis, high temperature plasma diagnostics and to the design and calibration of x-ray astronomy measurements.

Recently there has been a growing interest in the field of X-Ray MicroFluorescence (XRMF) for analyzing small areas (with sizes greater than about 10 microns diameter). Several recent papers have described prototype systems for this kind of analysis, with particular emphasis on the elemental imaging applications. However, the technique of small-area XRF analysis is not new. For example, Bertin gives an excellent review of much of the earlier work (up to the late 1960s), which used a variety of focusing (with curved crystals) or collimation techniques. Several wavelength dispersive spectrometer systems were modified for small-spot analysis. One of the earliest spectrometers was the X-ray Milliprobe developed by Adler and Axelrod, which employed curved crystals.

Mercuric iodide (HgI2) with high atomic numbers of 80 and 53 for the components, and wide bandgap (2.1 eV) has been considered a potentially useful material for gamma ray spectroscopy for the last number of years. Considerable effort by numerous groups has been directed toward purification and growth of large single crystals of this material. Even with continuing improvement, however, the material is still characterized by good electron transport properties and only modest to poor hole transport behavior. Interesting results nevertheless have been reported in mid-range gamma ray spectroscopy using “up to millimeter thick sections of HgI2. One question always asked is: has the fundamental of lattice scattering etc. been reached in increasing hole transport behavior in this material? There is interesting speculation at this time that this may not be so.

Residual stresses are found in the majority of multilayer thin film structures used in modem technology. The measurement and modeling of such stress fields and the elucidation of their effects on structural reliability and device operation has been a “growth area” in the literature, with contributions from authors in various scientific and engineering disciplines.

In this paper a review of the definitions of the residual stresses used by the authors in the various disciplines is presented and the mechanisms by which residual stresses may form in thin film systems is discussed.

An X-ray powder diffraction analysis has been performed on several samples from the naturally occuring patina of the Statue of Liberty. This work, which was conducted as a service to the National Park Service as part of the restoration activities for the Statue, was performed to assess the impact of acid deposition on the phase composition of the patina. Samples of the patina that were obtained from various locations on the copper skin of the Statue were found to consist primarily of the basic copper sulfate known as brochantite or CuSO4·3Cu(OH)2. Another less stable form of basic copper sulfate CuSO4·2Cu(OH)2 known as antlerite was also observed in samples taken from areas that are more exposed to the incoming weather in New York harbor. The presence of antlerite supports the contention that acid deposition is promoting undesirable changes in the phase composition of the patina. Analyses were also performed on patina samples that were taken from pieces of the Statue's copper skin that had been removed in the years 1905 and 1980. X-ray powder diffraction of the corrosion product on the 1905 sample showed that it consisted primarily of the stable brochantite phase, while the 1980 sample displayed both copper chlorides as well as the less stable antlerite. Both samples also contained cuprite (Cu2O) which appears to have formed prior to either of the sulfates.