%0 Conference Paper
%F Oral 
%T Structural transformations of methane adsorbed in MOF-5 model framework
%+ Matériaux divisés, interfaces, réactivité, électrochimie (MADIREL)
%+ Laboratoire Charles Coulomb (L2C)
%A Kuchta, B
%A Firlej, Lucyna
%A Formalik, Filip
%A Llewellin, P
%< avec comité de lecture
%Z L2C:18-320
%B 8th International Workshop 'Characterization of Porous Materials: from Angstroms to Millimeters' (C
%C Delray Beach, United States
%8 2018-05-06
%D 2018
%Z Physics [physics]/Physics [physics]/Computational Physics [physics.comp-ph]
%Z Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci]Conference papers
%X Phase changes are ubiquitous in nature, and transformations between solid structures represent a large group of them. They are usually reported on phase diagrams, as coexistence lines between different structures. The phase diagrams, well established for macroscopic 3-dimensional (3D) materials, change drastically when the material’s dimensions are reduced to few nanometers, or if the material is confined in a nano-pore. At the nanoscale the positions of coexistence lines on the phase diagrams are shifted and their new locations depend mainly on the size and shape of the nano-confinement, the structure of the confining walls, and their interaction with the confined substance. Here we show that it is possible to induce structural transformations in a confined system by simply varying the number of molecules adsorbed in the pore. We found that the mechanism of these novel, adsorption-induced structural transformation in nano-pores differs from that of well-known capillary condensation. The confined, equilibrium structures are not characterized by mean positions of molecules but rather by a probability distribution of molecular positions around adsorption centres. The character of transformation depends on temperature: it is strongly discontinuous at low temperature but evolves into a continuous transition when the temperature increases.
%G English
%L hal-01938872
%U https://hal.science/hal-01938872
%~ CNRS
%~ UNIV-AMU
%~ L2C
%~ INC-CNRS
%~ MADIREL
%~ MIPS
%~ UNIV-MONTPELLIER
%~ TEST-HALCNRS
%~ UM-2015-2021
%~ TEST2-HALCNRS