Pr1+xBa2−xCu3O7±δ solid solution was investigated by means of X-ray powder diffraction and Rietveld analysis. Single-phase PrBa2Cu3O7±δ (Pr123) can be synthesized under a Pr-rich condition by sintering at 950 °C in air. The solubility of Pr1+xBa2−xCu3O7±δ solid solution is 0.08≤x≤0.80. The structure of Pr1+xBa2−xCu3O7±δ is orthorhombic for 0.08≤x<0.30, and transforms into tetragonal for 0.30≤x≤0.80. To form single-phase Pr123, the Ba sites in the Pr123 structure are partially occupied by excess Pr ions, and the smallest amount of excess Pr is x=0.08. Meanwhile, all Ba ions stay in the Ba sites.

Crystal structures of types II and III chlorothalonil, 2,4,5,6-tetrachloro-1,3-dicyanobenzene, (C8Cl4N2) were solved by applying Monte Carlo simulated annealing techniques to X-ray powder diffraction data and refined using the Rietveld method. Both types of chlorothalonil crystallize in monoclinic symmetry (space group P21 and two molecules per unit cell). Lattice parameters are: a=8.1615(18) Å, b=9.4191(19) Å, c=6.4728(14) Å, β=93.7307(64)° and V=497.8 Å3 for type II, and a=8.6003(10) Å, b=9.2382(11) Å, c=6.3024(7) Å, β=96.2152(60)° and V=498.5 Å3 for type III. The structures of both types of chlorothalonil are stacked by two coplanar molecular sheets paralleled to the b-axis. The adjacent two paralleled molecules in type II are on the same plane, while those in type III are on two different parallel planes.

The crystal structure of La0.67Ca0.33Mn0.80Cu0.20O3 (LCMCO) compound was determined from laboratory X-ray powder diffraction data and refined by the Rietveld method. LCMCO is isostructural with La0.67Ca0.33MnO3 (LCMO). The crystal data are: La0.64Ca0.36Mn0.82Cu0.18O3.01, Mr=843.80, orthorhombic system, space group Pnma, a=5.4364(1) Å, b=7.6725(2) Å, c=5.4452(1) Å, V=227.124(8)Å3, Z=4, Dx=6.168 g∕cm3. In comparing with the Cu-free compound, subtle structural changes such as bond lengths and bond angles found in the Cu-doped compound may be responsible for the larger effects on the transport and magnetic properties when Cu partially substitutes for Mn in CMCO.

A new method, namely UACIEM, to extract reliable intensities of nonequivalent systematical overlapping reflections has been proposed and tested by simulated powder diffraction data from known crystal structures. Using both crystallographic and structural chemistry information, the method reconstructs diffraction intensities and solves a crystal structure through an iterative procedure. Our study shows that UACIEM is successful for cases where more than 30% of the total scattering power is located with precision from equivalent systematical overlapping reflections. The UACIEM process is not needed when equivalent systematical overlapping reflections are sufficient to reveal a crystal structure. UACIEM may fail in cases when: (i) only a small portion of the total scattering power (e.g., less than 7%) can be located, and (ii) most of the total scattering power (e.g., 95%) is located, but the atomic coordinates are not accurately known. The UACIEM method is superior to the simple equipartition methods for nonequivalent systematical overlapping reflections.

A qualitative phase identification system for crystalline mixtures is presented. The system provides up to five-phase qualitative identification using up to nine-peak filtration, and additive full peak matching based on the powder diffraction file of ICDD. It was implemented using Microsoft Visual C++, and runs under most common Windows systems. Screenshots and examples are included.

Ge–Si inverted huts, which formed at the Si∕Ge interface of Si∕Ge superlattice grown at low temperatures, have been measured by X-ray diffraction, grazing incidence X-ray specular and off-specular reflectivities, and transmission electron microscopy (TEM). The surface of the Si∕Ge superlattice is smooth, and there are no Ge–Si huts appearing on the surface. The roughness of the surfaces is less than 3 Å. Large lattice strain induced by lattice mismatch between Si and Ge is found to be relaxed because of the intermixing of Ge and Si at the Si∕Ge interface.

Fe–N thin films were deposited on glass substrates by dc magnetron sputtering under various Ar∕N2 discharge conditions. Crystal structures and elemental compositions of the films were characterized by X-ray diffraction and X-ray photoelectron spectroscopy. Magnetic properties of the films were measured using a superconducting quantum interference device magnetometer. Films deposited at different N2∕(Ar+N2) flow ratios were found to have different crystal structures and different nitrogen contents. When the flow ratios were 60%, 50%, and 30%, a nonmagnetic single-phase FeN was formed in the films. At the flow ratio of 10%, two crystal phases of γ′-Fe4N and ε-Fe3N were detected. When the flow ratio reduced to 5%, a mixture of α-Fe, ε-Fe3N, FeN0.056, and α″-Fe16N2 phases was obtained. The value of saturation magnetization for the mixture was found to be larger than that of pure Fe.

A Mg-stabilized triclinic tricalcium silicate form of type Ca3−xMgxSiO5, T3, was synthesized. Rietveld analysis using synchrotron X-ray powder diffraction data suggested that unlike the T1 form, the T3 structure was unmodulated. This refinement illustrated that the only existing model for a triclinic form of tricalcium silicate (T1) can be used to describe the nonmodulated T3 form.

The structures of SmAlSi and SmAlGe were determined by the powder diffraction method. These compounds have a tetragonal structure of LaPtSi type, which is a ternary substitutional variant of α-ThSi2. Both prototype structures have the same extinction rules, and as a result, the choice of the structural type must be based on very careful examination of the peak intensities. This was done with the aid of a Rietveld refinement, which indicates a better fit of the LaPtSi structure.

Heavy atoms dominate the X-ray scattering from many inorganic compounds like oxides and oxalates, and often only partial structures of these compounds can be obtained by X-ray powder diffraction data. Combining information from X-ray and neutron diffraction data is an advantage. Scattering contributions from the atoms are more evenly distributed in neutron diffraction data than in X-ray diffraction data. Neutron diffraction data can then be used to complete a structure partially solved with data from an X-ray diffraction pattern. Examples of heavy atom structures solved in the time period 1983–2004 using direct methods outlined above are presented.

A new method is introduced for the evaluation of experimental stress–strain dependence in thermally cycled thin films. The method is demonstrated on the analysis of an Al thin film on a Si(100) substrate characterized using in situ high-temperature X-ray diffraction 25–450 °C. Diffraction data are used to evaluate in-plane elastic strain in the film as a function of thermal strain originating from the mismatch of thermal expansion coefficients (TECs) between the film and the substrate. The magnitude of the thermal strain is calculated from experimental TECs of the film and the substrate at every measurement temperature. By relating in-plane stresses to thermal strains, an experimental stress–strain dependence for the Al thin film is obtained. The proposed method allows one to identify elastic behavior and to quantify plastic strain in the film. Finally, advantages of the method are discussed in particular its independence from using TECs reported in the literature.

X-ray power diffraction data for CrFe3NiSn5 are reported. Indexing the XRD power pattern and Rietveld refinement shows that the compound crystallizes in the hexagonal crystal system, space group P6mm (No. 183) with lattice parameters a=5.3168(1) Å, c=4.4261(1) Å, z=0.6 and Dcalc=8.011 g cm−3. The crystal structure of CrFe3NiSn5 is of the CoSn structure type with Fe, Cr and Ni disordered in the Co position.

Methods of chemical preparation and crystallographic data are reported for two new condensed phosphates: a polyphosphate of nickel and cesium, NiCs4(PO3)6, and a cyclotriphosphate of nickel and potassium, NiK4(P3O9)2. NiCs4(PO3)6 is rhombohedral with the following unit-cell dimensions: a=b=11.602(1) Å, c=9.078(1) Å, space group P−31c, V=1058.24(1) Å3, and Z=2. NiK4(P3O9)2 is triclinic with the following unit-cell dimensions: a=6.143(8) Å, b=6.80(1) Å, c=12.80(3) Å, α=102.8(3)°, β=89.7(2)°, γ=66.03(7)°, space group P−1, V=473.56(3) Å3, and Z=1.

The X-ray diffraction patterns of two organic acids 1-naphthalenesulfonic acid dihydrate and 2-naphthalenesulfonic acid hydrate were measured at room temperature. Complexes of these acids with 1,8-bis(dimethylamino)naphthalene (DMAN) were synthesized, purified and investigated by means of X-ray powder diffraction. 1-Naphthalenesulfonic acid dihydrate as well as its complex with 1,8-bis(dimethylamino)naphthalene crystallize in the monoclinic system with unit cell parameters refined to a=0.91531(8) nm, b=0.7919(1) nm, c=0.8184(1) nm, β=101.618(9)° space group P21/m (11) and a=1.7781(4) nm, b=2.0122(4) nm, c=1.2337(2) nm, β=96.54(3)°, space group C2/m (12), respectively. 2-Naphthalenesulfonic acid hydrate crystallizes in the orthorhombic system with a=2.2749(3) nm, b=0.7745(1) nm, c=0.591 36(9) nm, space group Pnma, whereas its complex with 1,8-bis(dimethylamino)naphthalene crystallizes in the triclinic system a=1.3969(6) nm, b=1.4292(5) nm, c=1.1741(6) nm, α=90.93(3)°, β=98.14(3)°, γ=113.93(3)°, space group P-1 (2).

X-ray powder diffraction data for a new calcium zirconium phosphate Ca7Zr(PO4)6 are reported. The sample was prepared by heating mixtures of CaCO3, ZrO2, and NH4H2PO4 in prescribed molar ratios at 1623 K. Powder diffraction data were collected with a laboratory X-ray source (Cu Kα) for refinement of unit-cell parameters and intensity measurement of individual reflections. Crystallographic data were Ca7Zr(PO4)6, cubic, I-43d (No. 220), a=0.98338(1) nm, V=0.95097(3) nm3, Z=2, and Dx=3.29 Mg m−3. This compound is most probably isomorphous with eulytite.