Transient Polymorphism in NaCl
Federico Giberti1,2, Gareth A Tribello1,2,3, Michele Parrinello1,2
1Department of Chemistry and Applied Biosciences, ETH Zurich, Zurich, Switzerland.
Abstract:
We introduce a new collective variable (CV) that can be used to increase the frequency with which nucleation events are observed in biased atomistic simulations. This CV forces the ions to aggregate into clusters but does not force the ions to order themselves in a particular pattern. We perform metadynamics simulations using this CV in order to examine nucleation in a solution of sodium chloride and find that for small cluster sizes the usual bulk rocksalt structure is less stable than a structure that resembles wurtzite.
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