| People | Locations | Statistics |
|---|---|---|
| Naji, M. |
| |
| Motta, Antonella |
| |
| Aletan, Dirar |
| |
| Mohamed, Tarek |
| |
| Ertürk, Emre |
| |
| Taccardi, Nicola |
| |
| Kononenko, Denys |
| |
| Petrov, R. H. | Madrid |
|
| Alshaaer, Mazen | Brussels |
|
| Bih, L. |
| |
| Casati, R. |
| |
| Muller, Hermance |
| |
| Kočí, Jan | Prague |
|
| Šuljagić, Marija |
| |
| Kalteremidou, Kalliopi-Artemi | Brussels |
|
| Azam, Siraj |
| |
| Ospanova, Alyiya |
| |
| Blanpain, Bart |
| |
| Ali, M. A. |
| |
| Popa, V. |
| |
| Rančić, M. |
| |
| Ollier, Nadège |
| |
| Azevedo, Nuno Monteiro |
| |
| Landes, Michael |
| |
| Rignanese, Gian-Marco |
|
Volkov, Sergey
in Cooperation with on an Cooperation-Score of 37%
Topics
Publications (8/8 displayed)
- 2024The intrinsic twinning and enigmatic twisting of aragonite crystalscitations
- 2023Reversible Ultrathin PtO$_x$ Formation at the Buried Pt/YSZ(111) Interface Studied In Situ under Electrochemical Polarizationcitations
- 2019Potential-Induced Pitting Corrosion of an $mathrm{IrO_{2}(110)-RuO_{2}(110)/Ru(0001)}$ Model Electrode under Oxygen Evolution Reaction Conditionscitations
- 2019Potential-Induced Pitting Corrosion of an IrO2(110)-RuO2(110)/Ru(0001) Model Electrode under Oxygen Evolution Reaction Conditionscitations
- 2018β-Ca11B2Si4O22: six-fold twinning, crystal structure and thermal expansioncitations
- 2017Operando X-ray Investigation of Solid Oxide Fuel Cell Model Electrodes
- 2016Operando X-ray Investigation of Electrode/Electrolyte Interfaces in Model Solid Oxide Fuel Cellscitations
- 2015Incommensurate modulation and thermal expansion of Sr3B2 + xSi1 − xO8 − x/2solid solutionscitations
Places of action
| Organizations | Location | People |
|---|
article
The intrinsic twinning and enigmatic twisting of aragonite crystals
Abstract
<jats:p>It is generally accepted that aragonite crystals of biogenic origin are characterized by significantly higher twin densities compared to samples formed during geological processes. Based on our single crystal X-ray diffraction (SCXRD) and transmission electron microscopy (TEM) study of aragonite crystals from various localities, we show that in geological aragonites, the twin densities are comparable to those of the samples from crossed lamellar zones of molluscs shells. The high twin density is consistent with performed calculations, according to which the Gibbs free energy of twin-free aragonite is close to that of periodically twinned aragonite structure. In some cases, high twin densities result in the appearance of diffuse scattering in SCXRD patterns. The obtained TEM and optical micrographs show that besides the twin boundaries (TBs) of growth origin, there are also TBs and especially stacking faults that were likely formed as the result of local strain compensation. SCXRD patterns of the samples from Tazouta, in addition to diffuse scattering lines, show Debye arcs in the<jats:inline-formula><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline" overflow="scroll"><mml:mrow><mml:msup><mml:mi>a</mml:mi><mml:mo>∗</mml:mo></mml:msup><mml:msup><mml:mi>b</mml:mi><mml:mo>∗</mml:mo></mml:msup></mml:mrow></mml:math></jats:inline-formula>plane. These Debye arcs are present only on one side of the Bragg reflections and have an azimuthal extent of nearly 30°, making the whole symmetry of the diffraction pattern distinctly chiral, which has not yet been reported for aragonite. By analogy with biogenic calcite crystals, we associate these arcs with the presence of misoriented subgrains formed as a result of crystal twisting during growth.</jats:p>