A natural olivine sample from a mantle peridotite xenolith has been studied by in situ high-temperature powder diffraction. The structure has been successfully refined from powder data at three temperatures (25, 600, and 800 °C) using the Rietveld method. The study shows that the full-profile technique is well suited for the structure analysis of high-temperature powder diffraction data. The results indicate that, in this temperature range, there is no significant ordering of the Fe,Mg cations in the two crystallographically independent octahedral sites. This has implications for the thermodynamic modeling of olivine at upper mantle conditions. The present experiments allowed measurement of the lattice thermal expansion of olivine in the temperature range 25–800 °C, and assessment of the temperature dependence of the isotropic atomic displacement parameters.

A simple device was developed for a moisture-proof X-ray diffraction analysis. The device consists of a simple plastic ring where one side was glued on with a thin film to let in the X-ray beam and the other side was covered with grease to seal onto a base plate. This device was later optimized by selecting a good adhesive to glue on the film, a very effective film to minimize the moisture intake, and an optimum ring height to maximize the X-ray intensity. Finally, this simple device was successfully verified that it can protect the anhydrous CaCl2 (hydrophilite) up to 4 days in ambient air.

With the Powder Diffraction File (1988), twelve different numerical search manuals with the number of entries per phase from one to four were used to identify the 237 experimental X-ray powder diffraction data sets collected from visually measured 57.3 mm diameter Debye-Scherrer films. Eighty-four percent of the experimental X-ray powder diffraction data have the same strongest reflection as the data in the Powder Diffraction File. For a single-phase unknown the most efficient numerical search manual type is a single entry per phase if used correctly and systematically; however, multiple entries do help in some instances. Up to seven groups must be searched in a single-entry numerical search manual to identify a phase.

The synthesis, thermal behavior, crystallographic and X-ray powder diffraction data, and infrared spectral data for Ca8ZnSi4O16Cl2 have been determined. This compound is cubic with isolated silicate tetrahedra.

Indexed experimental powder diffraction patterns of Tl,Pb-1223 and Tl-1223 are presented with a method of determining good cell parameters for the former awkward case where c/a almost exactly equals 4. For Tl,Pb-1223, a = 3.814±0.001 Å, c = 15.267±0.005 Å, for Tl-1223, a = 3.814±0.001 Å, c = 15.302±0.005 Å, both tetragonal, space group P4/mmm.

The crystal structure data have been determined by X-ray diffraction for three rare earth magnetic materials, Nd2Co14B, Pr2Co14B, and Pr2Fe14B. The data were evaluated with several computer programs desingned for that purpose. The crystal structure for Nd2Co14B and Pr2Fe14D determined by X-ray diffraction agree with those obtained earlier by neutron diffraction.