Do clathrates promote the nucleation of ice?

MATIAS H. FACTOROVICH; NAULLAGE, PAVITHRA M.; MOLINERO, VALERIA

Congreso; Gordon Research Conference on Chemistry and Physics of Liquids; 2019

Gordon Research Conference

We will address a problem related to methane-water mixtures. This system forms solid solutions at high methane pressures and low temperatures, which are known as clathrates. These clathrates, once formed, have the ability to survive in a metastable state at ambient pressure below 273K, this phenomenon is known as self-preservation. This self-preservation is made possible by the formation of an ice layer that covers the clathrate particles and prevents further gas loss. While several studies have been conducted on this phenomenon, the mechanism bywhich ice forms on decaying clathrates has not been fully explained yet. Here, we use molecular simulations in combination with biased methods, thermodynamic analysis, and classical nucleation theory to investigate possible scenarios for the formation of this ice sheet: heterogeneous nucleation atthe clathrate/vapor or clathrate/liquid interfaces and homogeneous nucleation from supercooled water