The ICE group won prizes at this year’s Thomas Young Centre student day! With his presentation entitled “Role of Structure and Dynamics in Heterogeneous Ice Nucleation: A Tale of Two Brothers?” Martin won the prize for the best talk given amongst 12 shortlisted final-year PhD students in the TYC. For his contribution “A Machine Learning Potential for Graphene” in the exhibition of more than 30 posters Patrick was awarded the prize for the best poster. They were judged by a panel of experts including Andrea Taroni, editor in chief of Nature Physics, Royal Society Fellow Sally Price and TYC representatives Dario Alfè, Michail Stamatakis, Arash Mostofi and Alston Misquitta. Congratulations!
Martin’s paper together with Gabriele, Fabio, Silvio and Angelos has been published in Nature Communications!
In this paper we investigate pre-critical fluctuations and what they can tell us about the heterogeneous nucleation event. Pre-critical fluctuations are the earliest occurrences of crystalline clusters in a supercooled liquid and thus readily probed in simulations such as molecular dynamics. We find that they can tell us which polymorph will form but they are not trivially indicative (as often assumed) of the nucleation enhancement. This also means that the commonly applied heterogeneous classical nucleation theory makes an error when comparing heterogeneous and homogeneous nucleation events where different polymorphs have formed. As a side, in this work we also find a simple recipe of avoiding stacking-disorder in hetergeneous ice nucleation during the nucleation stage.
Martin’s paper together with Laurent, Ming, Gabriele, Andrea and Angelos has been published in JCP Communications! In this work we studied wetting of water droplets on a substrate. With the help of metadynamics we have uncovered that for cutoffs that are more than commonplace in the MD community (2-3 sigma) the underlying free energy profile of wetting can exhibit metastable wetting states. Those states are not only unphysical but they can also be very hard to detect and could therefore corrupt computational results and interpretations. Our results show that a cutoff should not be treated as a fitting parameter in the development of force fields since the underlying physics can be inherently different and thus one needs to use long-range versions or very large cutoffs if one wants to be absolutely sure. Read the paper online or on our publications page.
Philipp’s and Martin’s paper was published in Physical Review B! In this article they computed the ice nucleation ability of numerous model hydroxylated substrates with diverse OH group arrangements. For the substrates considered, they find that neither the symmetry of the OH patterns nor the similarity between a substrate and ice correlate well with the IN ability. Instead, they find that the OH density and the substrate-water interaction strength are useful descriptors of a material’s IN ability. This insight allows the rationalization of ice nucleation ability across a wide range of materials, and can aid the search and design of novel potent ice nucleators in the future. Check out the article online or on our publications page.