TY  - JOUR
A1  - Farges, Francois
A1  - Djanarthany, S
A1  - de Wispelaere, S
A1  - Munoz, Manuel
A1  - Magassouba, B
A1  - Haddi, A
A1  - Wilke, Max
A1  - Schmidt, C.
A1  - Borchert, Manuela
A1  - Trocellier, P
A1  - Crichton, W
A1  - Simionovici, Alexandre
A1  - Petit, Pierre-Emanuel
A1  - Mezouar, Mohamed
A1  - Etcheverry, M. P.
A1  - Pallot-Frossard, I
A1  - Bargar, John Reeder
A1  - Brown, G. E.
A1  - Grolimund, D
A1  - Scheidegger, A
T1  - Water in silicate glasses and melts of environmental interest : from volcanoes to cathedrals
N2  - In silicate glasses and melts, water acts according to two main processes. First, it can be dissolved in high temperature/high pressure melts. Second, it constitutes a weathering agent on the glass surface. A number of in-situ x- ray absorption fine structure (XAFS) studies for Fe, Ni, Zr, Th and U show that the more charged cations (Zr, Nb, Mo, Ta, Sn, Th and U) are little affected by the presence of dissolved water in the melt. In contrast, divalent iron and nickel are highly sensitive to the presence of water, which enhance nucleation processes, for example, of phyllosilicates at the angstrom-scale. Such information provides additional constraints on the role of water deep in the Earth, particularly in magmatology. By contrast, the weathering of glass surfaces by water can be studied from a durability perspective. Experimental weathering experiments Of nuclear waste glasses performed in the laboratory show a variety of surface enrichments (carbon, chlorine, alkalis, iron) after exposure to atmospheric fluids and moisture. Mn-, and Fe-surface enrichments of analogous glasses of the XIVth century are related to the formation of Mn and Fe oxy/ hydroxides on the surface. The impact on the glass darkening is considered in terms of urban pollution and mass tourism
Y1  - 2005
ER  - 
TY  - JOUR
A1  - Porȩba, Tomasz
A1  - Racioppi, Stefano
A1  - Garbarino, Gaston
A1  - Morgenroth, Wolfgang
A1  - Mezouar, Mohamed
T1  - Investigating the structural symmetrization of CsI3 at high pressures through combined X-ray diffraction experiments and theoretical analysis
JF  - Inorganic chemistry
N2  - ABSTRACT: Structural evolution of cesium triiodide at high pressures has been revealed by synchrotron single-crystal X-ray diffraction. Cesium triiodide undergoes a first-order phase transition above 1.24(3) GPa from an orthorhombic to a trigonal system. This transition is coupled with severe reorganization of the polyiodide network from a layered to three-dimensional architecture. Quantum chemical calculations show that even though the two polymorphic phases are nearly isoenergetic under ambient conditions, the PV term is decisive in stabilizing the trigonal polymorph above the transition point. Phonon calculations using a non-local correlation functional that accounts for dispersion interactions confirm that this polymorph is dynamically unstable under ambient conditions. The high-pressure behavior of crystalline CsI3 can be correlated with other alkali metal trihalides, which undergo a similar sequence of structural changes upon load.
Y1  - 2022
U6  - https://doi.org/10.1021/acs.inorgchem.2c01690
SN  - 0020-1669
SN  - 1520-510X
VL  - 61
IS  - 28
SP  - 10977
EP  - 10985
PB  - American Chemical Society
CY  - Washington
ER  -