Crystalline phases present in pigments scratched off the surfaces of some decorated ceramic sherds belonging to the Cucuteni Neolithic culture were successfully identified using synchrotron radiation X-ray diffraction at Daresbury Laboratory. The ceramic sherds were selected from a collection of the National Museum of Romanian History in Bucharest. The synchrotron radiation X-ray diffraction analysis revealed that the black-color pigments on the surface of a number of sherds were produced by a variety of jacobsite (Fe2MnO4) phases; magnetite (Fe3O4) was also found in one of the sherds. The red color was derived from clay slips with a high content of hematite (Fe2O3). Calcite (CaCO3) was found in the white pigments; its presence was explained as being related to postburial deposition processes. Conclusions on technological aspects, provenance, and conservation issues are given.

Calcium carbonate crystals were prepared via a simple precipitation reaction of sodium carbonate with calcium chloride from mixed solutions of various amphiphilic organic solvents and water in the presence of cetyltrimethylammonium bromide at 25 and 60 °C. Our analysis shows that amphiphilic organic solvents and temperature have large influences on the structure and morphology of CaCO3. X-ray diffraction patterns show that single-phase hexahedral calcite was formed at 25 °C, and orthorhombic aragonite was obtained at 60 °C. Mixtures of major amounts of long aragonite crystals and minor amounts of calcite particles were also obtained at 60 °C in the methanol and the acetone solutions. Scanning electron microscopy images show that CaCO3 particles and aggregates with various morphologies, such as large solid and hollow hexahedral crystals and small round granules of calcite as well as glass-like and wheat-like aggregates of aragonite, were obtained depending on the experimental conditions. Based on the experimental results, a conclusion on the effects of temperature and amphiphilic organic solvents on the crystal structure and morphology are made.

A series of synthetic calcium silicates has been produced comprising nano-sized plates. The starting calcium silicate referred to as nano-structured calcium silicate, NCS, appears itself X-ray amorphous but contains impurities of calcite. These impurities decompose during the dry thermal conversion of the material into wollastonite. NCS can be enriched with calcium or silicon, respectively. The silicon enriched NCS can be hydrothermally transformed into a sheet material related to Ca7Si16O38(OH)2. The X-ray pattern of this material was sufficient to allow the calculation of its unit cell with a comparatively high figure of merit. The calcium enriched NCS can form two very distinctly different ceramic materials upon hydrothermal treatment, one a band material (formed below 200 °C) and the other a rose petal shaped material (formed above 210 °C). The X-ray diffraction patterns could not be resolved. The fit between the observed and calculated patterns was less than 50% as expressed in comparatively low figures of merit (unusually <20), which is attributed to calcium carbonate impurities in the samples disrupting the long range order. The patterns of these calcium enriched samples could be best compared to those of tobermorite or truscotite.

A general least-squares technique for X-ray diffraction line broadening analysis has been developed. The technique can be used to determine single, double, and triple line broadening effects caused by small particle sizes, microstrain, stacking faults, or all three presented in a closed-packed hexagonal nanomaterial. The technique was applied to characterize the microstructure of β-Ni(OH)2, a negative electrode material in nickel-metal hydride (NiMH) batteries. Double line broadening effects caused by both small crystallite sizes and stacking faults in β-Ni(OH)2 were detected and analyzed. Triple line broadening effects caused simultaneously by small crystallite sizes, microstrain, and stacking faults were detected in β-Ni(OH)2 after activation and charge-discharge cycle tests. The triple line broadening effects were found to be selective and most pronounced for diffraction lines with h−k=3n±1. The broadening effects were larger when l=even, but smaller when l=odd. The shape and the average size of the crystallites, microstrain, and stacking fault probability in β-Ni(OH)2 changed dramatically after activation and charge-discharge cycles. The method was also applied to characterize and investigate the microstructure of nano ZnO materials. Results indicate that no selective broadening appears in the XRD patterns of the nano ZnO materials. The average crystallite sizes were different slightly, and the stacking fault probabilities differed significantly with different dopants.

A lattice thermal expansion study on Li2NiMn3O8, a high-voltage cathode material for lithium-ion batteries, was carried out by high-temperature X-ray diffraction from room temperature to 973 K. Rietveld refinement of a high-quality room-temperature diffraction pattern confirmed that Li2NiMn3O8 has the cubic Al2MgO4 spinel type of crystal structure. The analysis of the high-temperature X-ray diffraction patterns showed that the Li2NiMn3O8 structure remained stable and no phase transition was detected over the temperature range from 298 to 973 K. As expected, the value of lattice parameter a or unit cell volume V increases with increasing temperature. The increase in a or V is linear only in the low-temperature region and nonlinear over the entire temperature range from 298 to 973 K. Least-squares analysis of the data for a or V showed the thermal expansion of a or V for Li2NiMn3O8 can best be fitted by a 3-degree polynomial function of temperature. The linear thermal expansion coefficients for a and V averaged over the entire temperature range from 298 to 973 K were also calculated, and αTa=1.10×10−5 K−1; αTV=3.29×10−5 K−1.

The crystal structure of titanium-tin tellurium oxide Sn0.59Ti0.41Te3O8 has been determined using X-ray powder diffraction techniques. At room temperature, the title compound crystallizes in cubic space group Ia-3, with lattice parameter a=11.05515(6) Å. Rietveld refinement of the structure led to final confidence factors Rp=0.0395 and Rwp=0.0577. The structure of Sn0.59Ti0.41Te3O8 consists of isolated Ti/SnO6-octahedra slightly deformed in the a direction. The TeO4E [E=lone pair of Te(IV) atoms] groups are located between the octahedra ensuring the stability of the structure by Ti/Sn-O-Te bonding contacts. Only one peak in thermal behavior was detected for this compound at 488 K by differential scanning calorimetry experiment. An IR spectroscopic study is employed as a means to obtain preliminary structural information and shows the presence of the Ti/SnO6 and TeO4E groups. This result is later confirmed by X-ray diffraction studies.

Synthesis and structure of two phosphates belonging to the ternary Sb2O5–In2O3–P2O5 system are realized. Structures of SbV1.50InIII0.50(PO4)3 and (SbV0.50InIII0.50)P2O7 phases, obtained by solid state reaction in air at 950 °C, were determined at room temperature from X-ray powder diffraction using the Rietveld method. SbV1.50InIII0.50(PO4)3 have a monoclinic (space group P21/n) distortion of the Sc2(WO4)3-type framework. Its structure is constituted by corner-shared SbO6 or InO6 octahedra and PO4 tetrahedra. Monoclinic unit cell parameters are a=11.801(2) Å, b=8.623(1) Å, c=8.372(1) Å, and β=90.93(1)°. (Sb0.50In0.50)P2O7 is isotypic with (Sb0.50Fe0.50)P2O7 and crystallizes in orthorhombic system (space group Pna21) with a=7.9389(1) Å, b=16.0664(2) Å, and c=7.9777(1) Å. Its structure is built up from corner-shared SbO6 or InO6 octahedra and P2O7 groups (two group-types). Each P2O7 group shares its six vertices with three SbO6 and three InO6 octahedra, and each octahedron is connected to six P2O7 groups.

Polycrystalline BaTi1−x(Zn1/3Nb2/3)xO3 (x=0.025 and 0.9) compounds were synthesized successfully and studied by XRD and dielectric measurements. The effects of the Ti/(Zn,Nb) ratio on the structure and dielectric properties of the compounds were investigated. XRD results indicated that the crystal structure of the x=0.09 compound is cubic perovskite with space group Pm3m and a=4.0095(4) Å. For the x=0.09 compound, a splitting of the (200) peak was observed near 40.2°, indicating that the crystal structure changed from cubic to tetragonal, with space group P4mm, a=4.026(4) Å, and c=4.0091(4) Å. Rietveld refinement of the crystal structures led to final confidence factors Rp=0.0353 and Rp=0.0349 for x=0.025 and 0.9, respectively. Dielectric measurements showed a relaxor behavior present in BaTi0.1(Zn1/3Nb2/3)0.9.

Evidence for the recently described 2M2 polytype of brochantite from X-ray powder diffraction investigation of secondary alteration products of ore material from the Pierre Plate Mine, Vizille, Isère, France is presented. This report is the first to describe the 2M2 polytype from locations outside of Italy and through the use of powder XRD methods. In the procedure used herein, developed in a study by Merlino et al. [Eur. J. Mineral 15, 267–275 (2003)], we have used family reflections, common to both main types of brochantite, as the source of approximate cell parameters from which we obtain positions of characteristic reflections to demonstrate the unique choice of polytype, before final refinement stage. This method demonstrates that the determination of polytype is possible from powder data, for samples typical of both geological and urban environments. Least-squares refined cell parameters for the 2M2 polytype from Pierre Plate are a=12.7409(8) Å, b=9.8371(6) Å, c=6.0109(3) Å, and a=90.135(9)°, constrained in space group P21/n11.

A ternary phase was revealed in Al-Ni-Re in a small compositional range around Al73.5Ni18.5Re8. Using powder X-ray diffraction and electron diffraction, it was found to have an orthorhombic structure with a=10.048(3) Å, b=15.423(8) Å, and c=8.367(3) Å.

X-ray powder diffraction data for five new bismuth yttrium gadolinium oxide compounds synthesized by solid state reaction method are reported. The unit cell dimensions were determined from X-ray diffraction methods, using CuKα radiation, and evaluated by indexing programs. The cubic phase was the sole crystalline phase detected by X-ray diffraction analysis in Bi0.88Y0.06Gd0.06O1.5, Bi0.88Y0.08Gd0.04O1.5, Bi0.82Y0.09Gd0.09O1.5, Bi0.82Y0.12Gd0.06O1.5, and Bi0.82Y0.06Gd0.12O1.5 samples with lattice constants of a=5.5371(1) Å, a=5.5368(1) Å, a=5.5303(2) Å, a=5.53487(8) Å, and a=5.5279(1) Å, respectively. The results are in good agreement with those reported for bismuth yttrium oxide (Bi0.75Y0.25)O1.5 (PDF 01-084-1450).

X-ray powder diffraction data for ErH2−xDx formed by hydrogen (i.e., protium)–deuterium loading of Er metal are reported. Lattice parameters for the varying hydrogen–deuterium compositions followed Vergard’s law behavior. The cubic lattice parameter at room temperature for ErH2−xDx obeys a linear relationship according to the formula a=5.1287−1.1120×10−4⋅x, where a is the lattice parameter of the fluorite-type structure and x is the mole percent of deuterium. Microstrain measurements suggest a possible ordering of hydrogen and deuterium in the composition ErH1D1.

Reported results for four new cubic compounds NdMMgMn2O6 (M=Li, Na, K, Cs) are questionable and cast doubt on the existence of such compounds. The lattice constants and relative intensities are essentially the same regardless of the nature of M; the X-ray diffraction patterns may be indexed with the lattice constants divided by √8, which result in much better figures of merit and a=0.3861 to 0.3883 nm, close to the subcell parameter of non-stoichiometric pseudocubic NdMnO3.

Corrections are made to two equations and one table value in “Thermal expansion of anatase and rutile between 300 and 575 K using synchrotron powder X-ray diffraction” [Powder Diffr. 22, 352–357 (2007)].