Six acentric tartrates and tartrato-antimonates have been investigated by means of X-ray powder diffraction. Single crystals were obtained by evaporation from aqueous solutions. The compounds have attracted attention because of their electrostrictive and electro-optical effects. Complete crystal data for the six compounds are reported. X-ray powder diffraction patterns for Rb2C4H4O6 and Ca [Sb2{C4H2O6}2]·2H2O are given.

The Level III Powder Diffraction File Computer Database can be used for many purposes beyond phase identification. The data file as received from the ICDD must be implemented via a data management system for efficient utilization. The results of one such implementation, and applications using the Mineral Powder Diffraction Subfile are reported. The applications include studies of space group statistics and density distributions as well as searches for cubic sulfide and uniaxial potentially pyroelectric minerals.

An analysis of the microstructure of nanocrystalline cerium oxide produced by thermal decomposition of cerium (IV) oxide nitrate at temperatures in the range 230° to 960 °C is described. Parameters describing the breadths and shape of X-ray diffraction line profiles were obtained by means of pattern decomposition and a method based on the Voigt function was used to obtain information on the temperature dependence of the microstructure. No marked anisotropy in size and strain broadening was observed. It was found that the crystallites are on average spherical, the dimensions increasing significantly with formation temperature, while microstrains decrease with annealing temperature. The results of size determinations were compared with SEM measurements. They suggest a competition between the crystallite growth and “particle” growth processes in the initial sintering of the loosely packed cerium oxide powder.

The silicate compound, K3Nb3O6Si2O7, has been synthesized by solid-state reaction. Single crystals were obtained; they crystallized with the hexagonal space group P2c. Refined unit-cell parameters are: a = 9.0377(3), c=8.0465(7)Å, V=569.18(5)Å3, Z=2, Dm = 3.84(4), Dx=3.851. Powder diffraction data are reported.

Crystallographic data for Ni0.41Zn0.60Cu0.01Fe2.04−xSbxO4+δ (0.01≤x≤0.12) ferrites are significantly influenced by small additions of antimony. XRD analysis reveals that changes in crystal data for small Sb substitutions differ markedly from those for greater Sb substitutions. The differences are due to the contribution of the Sb ion. Complete crystal data for six solid solution compositions are reported. An X-ray powder diffraction pattern for Ni0.41Zn0.60Cu0.02Sn0.01Fe2.02Sb0.02O4+δ is given.

The kinetics of γ'-phase formation in a Ni-base superalloy were studied. The data (pairs of cps and 2θ) were processed by the deconvolution program (Wiedemann, Unnam and Clark, 1987), which was rewritten in FORTRAN and installed on an IBM/VM and a VAX/VMS host computer. Optimal program parameters were found. Pure nickel was used as a standard. The only evidence obtained from the raw data is that the early stage of the aging process is accompanied by broadening. Deconvolution resolved the peaks into three kinds of diffraction lines: Ni(γ), precipitate (γ'), and undefined lines which have been interpreted as satellites. The results show that our X-ray diffraction lines are composed of the main diffraction lines of nickel-base A1 type alloy and additive satellites. In an advanced stage of aging the satellites assume the typical diffraction pattern of γ' phase.

Patterns useful for identification are obtained by automated diffractometer methods. The lattice constants from the experimental work are refined by least-squares methods; reflections are assigned hkℓ indices consistent with space group extinctions. Relative intensities, calculated densities, literature references, and other relevant data are included.

Cu2Th4(MoO4)9 is cubic: a=14.4856(1) Å, space group I4¯3d, Z=4. Its crystal structure was recently determined using a single crystal. The results of chemical study allow one to reject the existence of Li4Th7(MO4)16 and La(MO4)(ReO4) compounds with M=Mo, W, reported as isostructural with Cu2Th4(MoO4)9. Precise X-ray powder patterns are established for Cu2Th4(MoO4)9 and isotypic compounds Li2Th4(MoO4)9, Li2Th4(WO4)9, and La4(MoO4)3(ReO4)6.

Crystal data are given for synthetic mixed bariumstrontium sulfates, and a powder pattern for (Ba0.50Sr0.50)SO4 is presented. Taken with previously published data for the end-member sulfates, we verify the nonlinear behavior of the unit-cell edges with composition, and present tables of interpolated data from which d-spacings for intermediate compositions can be calculated. The use of these data for analysis of complex natural samples by use of the 121 peak is described.

The crystal structures of solution-grown and melt-grown polycrystalline samples of n-hexatetracontane (n-C46H94) in the temperature range 293–359 K have been investigated by X-ray powder diffraction. The solution-grown sample has an orthorhombic structure, with space group Pbc21 and cell dimensions a=4.952 Å, b=7.424 Å, and c=120.95 Å. While heating this sample a gradual transition to a monoclinic phase takes place, with onset temperature 335 K. At temperatures close to the melting point two configurations of the ab plane have been observed. Cooling a sample from the melt results in a mixture of a monoclinic and an orthorhombic structure. Rietveld refinements of the structures of solution-grown and melt-grown samples at 293 K have been performed.