Preview: Forthcoming article in Acta Crystallographica Section B: Structural Science
Forthcoming article in Acta Crystallographica Section B Structural Science, Crystal Engineering and Materials
Acta Crystallographica Section B: Structural Science, Crystal Engineering and Materials publishes scientific articles related to the structural science of compounds and materials in the widest sense. Knowledge of the arrangements of atoms, including their
Characterization of fluorine-centered `F⋯O' σ-hole interactions in the solid-state
We report the experimental observation of a `unique' and `rare' F⋯O interaction, involving two electronegative atoms, having the characteristics of `short interatomic distance' and `high directionality' that provide robustness to the crystal packing. The characterization of these F⋯O contacts via different computational procedures establish the interaction to be dispersive in nature and the mutual polarization of an O atom by F and vice versa provides real physical insights into the role of atomic polarizability in interacting atoms in molecules in crystals.
(Na,□)5[MnO2]13 nanorods: a new tunnel structure for electrode materials determined ab initio and refined through a combination of electron and synchrotron diffraction data
Octahedral molecular sieves (OMS) attract increasing interest in the search for novel electrode materials for energy storage and water desalination. While a nanometric particle size is desirable for such applications, this makes ordinary single-crystal characterization difficult and many OMS structures are still waiting for elucidation. Here we present the long awaited structure of a well known material, (Na,□)5[MnO2]13, resolved by a combination of electron diffraction tomography, dynamical scattering theory and X-ray powder Rietveld refinement. A new type of tunnel structure was found, able to explain previously reported electrochemical properties. This structure also suggests a possible mechanism for topotactic transformations between different manganese oxide OMS frameworks.
Hydrogen-substituted β-tricalcium phosphate synthesized in organic media
A hydrogen substitution mechanism, previously unknown in pure β-tricalcium phosphate, was discovered in crystals precipitated from ethylene glycol solutions. The structure was described by means of Rietveld refinement of powder X-ray diffraction data and corroborated by chemical analysis and IR spectroscopy.