165 research outputs found
Modelling the experimental electron density: only the synergy of various approaches can tackle the new challenges
This is an open-access article distributed under the terms of the Creative Commons Attribution Licence.Electron density is a fundamental quantity that enables understanding of the chemical bonding in a molecule or in a solid and the chemical/physical property of a material. Because electrons have a charge and a spin, two kinds of electron densities are available. Moreover, because electron distribution can be described in momentum or in position space, charge and spin density have two definitions and they can be observed through Bragg (for the position space) or Compton (for the momentum space) diffraction experiments, using X-rays (charge density) or polarized neutrons (spin density). In recent years, we have witnessed many advances in this field, stimulated by the increased power of experimental techniques. However, an accurate modelling is still necessary to determine the desired functions from the acquired data. The improved accuracy of measurements and the possibility to combine information from different experimental techniques require even more flexibility of the models. In this short review, we analyse some of the most important topics that have emerged in the recent literature, especially the most thought-provoking at the recent IUCr general meeting in Montreal.PM thanks the Swiss National Science foundation (Project 160157) for financial support. CL and NC are grateful to Universite de Lorraine, Agence Nationale de la recherche and
CNRS, for instrumental and financial support. JMG thanks CentraleSupélec, ANR and CNRS for financial support.Peer Reviewe
Monolithic Cells for Solar Fuels.
A tutorial review explaining the many processes occurring in photoelectrochemical cells for solar fuel production, and prospects for future developments
A breathing zirconium metal-organic framework with reversible loss of crystallinity by correlated nanodomain formation
The isoreticular analogue of the metal-organic framework UiO-66(Zr), synthesized with the flexible trans-1,4-cyclohexanedicarboxylic acid as linker, shows a peculiar breathing behavior by reversibly losing long-range crystalline order upon evacuation. The underlying flexibility is attributed to a concerted conformational contraction of up to two thirds of the linkers, which breaks the local lattice symmetry. X-ray scattering data are described well by a nanodomain model in which differently oriented tetragonal-type distortions propagate over about 7-10 unit cells
Etude par RMN des mécanismes de formation par hydrolyse des polycations d'aluminium
STRASBOURG-Sc. et Techniques (674822102) / SudocSudocFranceF
Revisiting the Identification of Structural Units in Aqueous Silicate Solutions by Two-Dimensional Silicon-29 INADEQUATE
Embajada europea en El Cair
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