The investigation of mixed monolayers adsorbed from solution: octane and nonane mixtures on graphite

Abstract

The combination of sensitive calorimetry, incoherent elastic neutron scattering and neutron diffraction has been used to demonstrate the formation of solid layers containing both octane and nonane adsorbed onto graphite from the binary alkane mixture. This combination of methods allow us to characterise the adsorbed layer in some detail including the absolute composition and melting temperature as a function of solution composition. The evidence presented here suggests that the two alkanes exist on the surface as patches of pure material not as a single crystal incorporating both alkanes.

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