An accelerative increase of the effective electron mobility with Mo content in SrFe_1−xMo_xO_3−δ is due to progressive formation of the Sr₂FeMoO₆ ordered areas with high electron mobility.

Electronic structure and total-energy calculations have been performed for $\mathrm{Cu}\mathrm{In}{\mathrm{Se}}_2$ and $\mathrm{Cu}(\mathrm{In},\mathrm{Ga}){\mathrm{Se}}_2$ using density-functional theory with generalized gradient corrections. To understand the fracture and deformation behavior in chalcopyrites, we calculated the cleavage and generalized stacking fault energies in $\mathrm{Cu}\mathrm{In}{\mathrm{Se}}_2$ and $\mathrm{Cu}(\mathrm{In},\mathrm{Ga}){\mathrm{Se}}_2$ and demonstrated a brittle character of crack propagation. Antiphase boundary and intrinsic stacking fault defects have low formation energies and are quite probable in these chalcopyrites. The main slip system and preferable cleavage plane should be $⟨\overline{1}10⟩\left(112\right)$ and (112), respectively. For the ⟨110⟩(001) and $⟨\overline{1}10⟩\left(112\right)$ dislocations in $\mathrm{Cu}\mathrm{In}{\mathrm{Se}}_2$, we predict a strong tendency for splitting in two partials.

The stability of the B2 Cu_xFe_1−x Al phases and the energy of defect formation are studied using ab initio band calculations. For B2 Cu_xFe_1−x Al alloys, vacancies in the 3d-metal sublattice and configurations with the minimum number of Fe-Cu bonds in the first coordination shell (including Fe antisite defects, which have a high local magnetic moment) are most stable. Complicated defect complexes with vacancies and displaced atoms, which are close to the atomic configurations of vacancy-ordered AlCu phases, can exist near the composition Cu_0.875Fe_0.125Al.

Nanotubes of manganese-doped zinc oxide Zn1 − xMn xO (0 ≤ x ≤ 0.2) were synthesized by heating the Zn1 − xMn x(HCOO)(OCH2CH2O)1/2precursor in air at 500°C. The precursor with extended crystals was...

The structure, oxygen non-stoichiometry, and defect equilibrium in perovskite-type PrBa_1−xSr_xFe₂O_6−δ (x = 0, 0.25, 0.50) synthesized at 1350 °C were studied. For all compositions, X-ray diffraction testifies to the formation of a cubic structure (S.G. $Pm\overline{3}m$), but an electron diffraction study reveals additional diffuse satellites around each Bragg spot, indicating the primary incommensurate modulation with wave vectors about ±0.43${\mathit{a}}^{*}$. The results were interpreted as a sign of the short-order in both A-cation and anion sublattices in the areas of a few nanometers in size, and of an intermediate state before the formation of an ordered superstructure. An increase in oxygen deficiency was found to promote the ordering, whereas partial substitution of barium by strontium caused the opposite effect. The oxygen content in oxides as a function of oxygen partial pressure and temperature was measured by coulometric titration, and the data were used for the modeling of defect equilibrium in oxides. The simulation results implied oxygen vacancy ordering in PrBa_1−xSr_xFe₂O_6−δ that is in agreement with the electron diffraction study. Besides oxidation and charge disproportionation reactions, the reactions of oxygen vacancy distribution between non-equivalent anion positions, and their trapping in clusters with Pr³⁺ ions were taken into account by the model. It was demonstrated that an increase in the strontium content in Pr_0.5Ba_0.5−xSr_xFeO_3−δ suppressed ordering of oxygen vacancies, increased the binding energy of oxygen ions in the oxides, and resulted in an increase in the concentration of p-type carriers.