Structure of liquid and glassy methanol confined in cylindrical pores

Abstract

We present a neutron scattering analysis of the density and the static structure factor of confined methanol at various temperatures. Confinement is performed in the cylindrical pores of MCM-41 silicates with pore diameters D=24 Å and D=35 Å. A change of the thermal expansivity of confined methanol at low temperature is the signature of a glass transition, which occurs at higher temperature for the smallest pore. This is an evidence of a surface induced slowing down of the dynamics of the fluid. The structure factor presents a systematic evolution with the pore diameter, which has been analyzed in terms of excluded volume effects and fluid-matrix cross-correlation. Conversely to the case of Van der Waals fluids, it shows that stronger fluid-matrix correlations must be invoked most probably in relation with the H-bonding character of both methanol and silicate surface. 2/33

Inhomogeneous relaxation dynamics and phase behaviour of a liquid crystal confined in a nanoporous solid

“…Our findings compare well with experimental results on the dynamics of "conventional" liquid condensates [8,84,[98][99][100][101][102][103] confined in nanoporous media. In particular, the observation of distinct core and shell molecular mobilities is also in good agreement with experimental studies on pore-confined liquid crystalline systems presented in the past [7, 58-66, 69, 70], most prominently with the work by Aliev et al discussed in the introduction.…”

Silica Surface Features and Their Role in the Adsorption of Biomolecules: Computational Modeling and Experiments

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Strings-to-Rings Transition and Antiparallel Dipole Alignment in Two-Dimensional Methanols

“…One of the simplest anisotropic molecules is methanol. As of yet, its liquid state in confined geometries has been studied only inside cylindrical nanotubes [9][10][11][12][13][14][15][16][17] .…”