Structure and fluctuations of the premelted liquid film of ice at the triple point

ABSTRACT

In this paper, we study the structure of the ice/vapour interface in the neighbourhood of the triple point for the TIP4P/2005 model. We probe the fluctuations of the ice/film and film/vapour surfaces that separate the liquid film from the coexisting bulk phases at basal, primary prismatic and secondary prismatic planes. The results are interpreted using a coupled sine Gordon plus Interface Hamiltonian model. At large length scales, the two bounding surfaces are correlated and behave as a single complex ice/vapour interface. For small length, on the contrary, the ice/film and film/vapour surfaces behave very much like independent ice/water and water/vapour interfaces. The study suggests that the basal facet of the TIP4P/2005 model is smooth, the prismatic facet is close to a roughening transition, and the secondary prismatic facet is rough. For the faceted basal face, our fluctuation analysis allows us to estimate the step free energy in good agreement with experiment. Our results allow for a quantitative characterisation of the extent to which the adsorbed quasi-liquid layer behaves as water and explains experimental observations which reveal similar activation energies for crystals grown in bulk vapour or bulk water.

GRAPHICAL ABSTRACT

Acknowledgements

The authors would like to thank A. Michaelides and B. Slater for providing us a copy of Ref. [46] prior to publication, as well as Eva G. Noya for helpful discussions.

Disclosure statement

No potential conflict of interest was reported by the authors.

ORCID

Luis G. MacDowell http://orcid.org/0000-0003-1900-1241

Additional information

Funding

The authors also wish to thank the Agencia Estatal de Investigación and Fondo Europeo de Desarrollo Regional (FEDER) under grant FIS2017-89361-C3-2-P. P.L. wishes to acknowledge additional support under grant FIS2015-72946-EXP.