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Abstract Maximum Entropy Method (MEM) is one of powerful tools for material science. We developed the program Z-MEM for evaluation of electron and nuclear density distribution by MEM analysis and Fourier synthesis. This code is designed by the multi-threading library OpenMP, so that the calculation performance is significantly improvements for MEM analysis. Z-MEM is bundled in Z-Rietveld , which is Rietveld software for X-ray and neutron powder diffraction, via the application programming interface (API). Since Z-MEM have equipped with the graphical user interface operations, users can perform from Rietveld refinement to MEM analysis seamlessly. [ABSTRACT FROM AUTHOR]

Abstract: Oxide ion conduction and phase transition phenomena have been investigated on La2−xPbxMo2O9−x/2 solid solutions (x≤0.6). X-ray and neutron diffraction experiments as well as thermal analyses indicate that a single phase of high-temperature polymorph (β-phase) is preserved down to room temperature for the composition of x≥0.06. In the solid solution range, ionic conductivity gradually decreases with Pb-substitution. Such phase transition and ionic conduction properties of La2−xPbxMo2O9−x/2 are quite similar to the Bi-substituted system, La2−xBixMo2O9, although ionic conductivity at lower temperatures is slightly higher in the former system than the latter with the same-amount of substitution. Room temperature neutron diffraction experiment suggests that oxide-ion deficiency is introduced mainly into O2 site by the charge compensation with Pb-substitution, which would contribute to a little enhancement in conductivity compared with Bi-substituted samples along with the variation of nearest O2 O3 bond length. [Copyright &y& Elsevier]

Abstract: The phase relationship of the TbO1.81–Mn3O4–Fe2O3 pseudo-ternary system synthesized at 1200°C was determined using X-ray and neutron diffraction method. Four solid solutions, Mn3−3 x Fe3 x O4 (0.00⩽ x ⩽0.278), Mn3−3 x Fe3 x O4 (0.291⩽ x ⩽0.667), Mn2−2 x Fe2 x O3 (0.89⩽ x ⩽1.00), and (Tb1− y Mn z Fe x )(Fe w Mn1− w )O3 (1−y + x + z ⩽1, 0.00⩽ w ⩽1.00) were found along with six two-phase regions and three three-phase regions. The boundaries were determined by several different methods such as phase disappearing, the Vigard’s law, and the lever rule. [Copyright &y& Elsevier]