The structure of chloride-based high-temperature molten salts and their mixtures

This thesis investigates the structural behavior of pure and mixed molten chloride salts at high temperatures, with implications for advanced energy technologies such as concentrated solar power and molten salt nuclear reactors. Creating a fundamental understanding of the relationships between the underlying atomic structure of molten salts and their thermodynamic properties is of critical importance for applications such as these. Recent developments presented herein help explain details about the atomic-level structure of melt mixtures including interesting phenomena such as structural heterogeneity.

Because structure is related to thermodynamics and thermodynamics is related to the phase behavior of these mixtures, these developments are highly relevant to practical applications. X-ray scattering measurements, which are the most common experimental tool to get at melt structure, cannot provide ion-specific information and instead are a property of the whole melt. Computer simulations help bridge the gap between experiments and the actual atomistic correlations between specific pairs of ion types. This thesis covers studies from the simple monovalent salts such as NaCl and KCl all the way to mixtures of salts including lanthanides and actinides.