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A hitherto unknown phase of sodium titanate, NaTi(3)O(6)(OH)·2H(2)O, was identified as the intermediate species in the synthesis of TiO(2) nanorods. This new phase, prepared as nanorods, was investigated by electron diffraction, X-ray powder diffraction, thermogravimetric analysis and high-resolution transmission electron microscopy. The structure was determined ab initio using electron diffraction data collected by the recently developed automated diffraction tomography technique. NaTi(3)O(6)(OH)·2H(2)O crystallizes in the monoclinic space group C2/m. Corrugated layers of corner- and edge-sharing distorted TiO(6) octahedra are intercalated with Na(+) and water of crystallization. The nanorods are typically affected by pervasive defects, such as mutual layer shifts, that produce diffraction streaks along c*. In addition, edge dislocations were observed in HRTEM images.

Reaction pathways to SnO(2) nanomaterials through the hydrolysis of hydrated tin tetrachloride precursors were investigated. The products were prepared solvothermally starting from hydrated tin tetrachloride and various (e.g., alkali) hydroxides. The influence of the precursor base on the final morphology of the nanomaterials was studied. X-ray powder diffraction (XRD) data indicated the formation of rutile-type SnO(2). Transmission electron microscopy (TEM) studies revealed different morphologies that were formed with different precursor base cations. Data from molecular dynamics (MD) simulations provide theoretical evidence that the adsorption of the cations of the precursor base to the faces of the growing SnO(2) nanocrystals is crucial for the morphology of the nanostructures.

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In multicomponent oxides of the transitional and rare-earth elements with perovskite structure (АВО 3 , А = rare-earth, В = transition metal) it is possible to improve the physicochemical and electrochemical properties with cation substitution in sites A and B. In this aim perovskite-like oxides of Sr-Bi-Ме-O systems (with Me = Cu [1][2][3], Co [4], Fe, Cr [5], Mn [6]) have been extensively studied. In this work we investigate the SrBi-Ni-O system where no structures have been published in spite of the fact that it should be possible to obtain multicomponent oxides which exhibit superconducting properties or are suitable for oxide fuel cell and membrane production. The samples with nominal composition Sr 3 Bi 2-х Ni x O 6-δ were prepared from nitride precursors and calcined in air or oxygen current at 900 °С during 10 -15 hours, followed by 20-30 hours at 1000 -1200 °С. Transmission electron microscopy showed the existence of at least 3 different phases: a tetragonal phase (a = 5.36 Å, c = 17.5 Å), a closely related orthorhombic phase (a o ≈ a t / √2, b o ≈ a t * √2, c o ≈ c t ) and a minority cubic phase (a = 33.6 Å). EDX yielded the cation ratio to be 22.0% Ni, 64.2% Sr and 13.8% Bi for the tetragonal phase, the oxygen being too light to be analyzed. In the case of such a mixture of phases with related cell parameters X-ray powder diffraction is useless for structure determination. We therefore conducted an electron crystallography study on the tetragonal phase. Due to the close relationship with the orthorhombic phase only few zone axes permit to distinguish between these two phases. Therefore, we only considered data from a single particle clearly identified as the tetragonal phase in this study. A total of 13 different zone axes were each recorded in selected area electron diffraction mode and with different precession angles up to 4.1°. From the observed extinctions the space group was determined to be I4/mmm or I4mm. For the structure solution we extracted the intensities from the 8 main zone axes yielding a total of 109 independent reflections with a resolution of 0.8 Å. The data were corrected by a geometrical Lorentz type factor and the structure was solved (R = 29%) using the SIR2008 program [7]. The solution contained all atoms except for one oxygen position. The structure can be described as formed by layers of edge sharing oxygen octahedra. The layers are connected via octahedron corners. In this contribution we compare the obtained structure to oxides containing other transition metal ions and discuss the subject of the missing oxygen position.[1] Kudo K., Nishizaki T., Okumura N. et al., J. of Ph. and Chem. of Solids, 2008, 69, 3022 Structural information is essential for understanding physical and chemical properties of materials. In order to gain structural information from nano crystalline materials diffraction data from single nano grains should be collected. In these cases nano electron diffraction is the technique of choice, as it can probe single crystals as small as 20 nm. Nevertheless...