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Confinement Effects on the Benzene Orientational Structure.

ABSTRACT: Liquids under confinement exhibit different properties compared with their corresponding bulk phases, for example, miscibility, phase transitions, and diffusion. The underlying cause is the local ordering of molecules, which is usually only studied using pure simulation methods. Herein, we derive experimentally the structure of benzene confined in MCM-41 using total neutron scattering measurements. The study reveals a layering of molecules across a pore, and four concentric cylindrical shells can be distinguished for a pore with the radius of 18?Å. The nanoscale confinement of the liquid has a major effect on the spatial and orientational correlations observed between the molecules, when compared with the structure of the bulk liquid. These differences are most marked for molecules in parallel configurations, and this suggests differences in chemical reactivity between the confined and bulk liquids.

SUBMITTER: Falkowska M

PROVIDER: S-EPMC6099463 | biostudies-literature | 2018 Apr

REPOSITORIES: biostudies-literature

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Confinement Effects on the Benzene Orientational Structure.

Falkowska Marta M Bowron Daniel T DT Manyar Haresh H Youngs Tristan G A TGA Hardacre Christopher C

Angewandte Chemie (International ed. in English) 20180313 17

Liquids under confinement exhibit different properties compared with their corresponding bulk phases, for example, miscibility, phase transitions, and diffusion. The underlying cause is the local ordering of molecules, which is usually only studied using pure simulation methods. Herein, we derive experimentally the structure of benzene confined in MCM-41 using total neutron scattering measurements. The study reveals a layering of molecules across a pore, and four concentric cylindrical shells ca ...[more]

PMID: 29446870

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