Publications by authors named "David Vie"
The structural evolution of metavanadate compounds under high pressure offers valuable insights into phase transitions and changes in material properties. This study explores the structural behavior of BaVO under pressures up to 12 GPa using powder X-ray diffraction and density-functional theory (DFT) simulations. The results indicate a phase transition from the ambient pressure orthorhombic phase (space group 222) to a monoclinic phase (space group 2) at 4 GPa, likely driven by the distortion of the vanadium oxide polyhedron.
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- * Results showed significant variations in element presence, such as arsenic and cadmium, based on the type of product, insect species, and country of origin.
- * The findings highlight the need for safety assessments of each insect species regarding element bioaccumulation and stress the importance of global approaches to ensure edible insects are safe as a sustainable protein source, indicating further research is necessary.
Band-Gap Energy and Electronic Transitions of NiWO Studied under High-Pressure Conditions.
J Phys Chem C Nanomater Interfaces
August 2023
Article Synopsis
- * It was found that the band gap of NiWO decreases with increasing pressure due to the contributions from Ni 3 states at the top of the valence band, with specific optical transitions observed at multiple energy levels.
- * The research confirms NiWO as a -type semiconductor, revealing that its resistivity decreases as pressure increases, supported by resistivity and Hall-effect measurements.
We report diffuse reflectivity measurements in InNbO, ScNbO, YNbO, and eight rare-earth niobates. A comparison with established values of the bandgap of InNbO and ScNbO shows that Tauc plot analysis gives erroneous estimates of the bandgap energy. Conversely, accurate results are obtained considering excitonic contributions using the Elliot-Toyozawa model.
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