A mechanism for ageing in a deeply supercooled molecular glass.

Chem Commun (Camb)

Center for Interstellar Catalysis and Department of Physics and Astronomy, Aarhus University, Ny Munkegade 120, Aarhus C, Denmark.

Published: June 2021

Measurements of the decay of electric fields, formed spontaneously within vapour-deposited films of cis-methyl formate, provide the first direct assessment of the energy barrier to secondary relaxation in a molecular glass. At temperatures far below the glass transition temperature, the mechanism of relaxation is shown to be through hindered molecular rotation. Magnetically-polarised neutron scattering experiments exclude diffusion, which is demonstrated to take place only close to the glass transition temperature.

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http://dx.doi.org/10.1039/d1cc01639cDOI Listing

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