Adsorption studies of acetone and 2,3-butanedione on ice surfaces between 193 and 223 K

International audienc

Adsorption of acetic acid on ice: Experiments and molecular dynamics simulations

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Experimental and Theoretical Adsorption Study of Ethanol on Ice Surfaces

International audienceAdsorption study of ethanol on ice surfaces were performed by combining experimental and theoretical approaches. The experiments were conducted using a coated wall flow tube coupled to a mass spectrometric detection. The surface coverage increases with decreasing temperature and with increasing ethanol concentrations. The obtained experimental surface coverages were fitted according to the B.E.T. theory in order to determine the enthalpy of adsorption ∆H ads and the monolayer capacity N M : ∆H ads =-57 ± 8 kJ mol-1 , N M = (2.8 ± 0.8)×10 14 molecule cm-2. The adsorption characteristics of ethanol on a proton disordered Ih(0001) ice surface were also jointly studied by performing classical molecular dynamics simulations. More specifically, the configurations of the molecules in their adsorption sites and the corresponding adsorption energies have been studied as a function of temperature and coverage. In the simulations, the saturation coverage is around N M = 3.2×10 14 molecule cm-2 , and corresponds to an adsorption energy equal to-56.6 kJ mol-1 , in good agreement with the experimental value. The results are discussed and compared with previous determinations for alcohols