|About this Abstract
||2022 TMS Annual Meeting & Exhibition
||Hume-Rothery Symposium on Connecting Macroscopic Materials Properties to Their Underlying Electronic Structure: The Role of Theory, Computation, and Experiment
||Molecular-scale Structure and Dynamics of Molten Salts: Simulations and Implications for Corrosive Processes
||Nick Winner, Haley Williams, Raluca Scarlat, Mark D. Asta
|On-Site Speaker (Planned)
||Mark D. Asta
Thermodynamic modeling of molten phases is often essential to predicting the behavior of high-temperature materials and their environmental interactions. In this talk we focus on molten mixtures of fluoride salts of interest in nuclear energy contexts. We employ ab-initio molecular dynamics simulations to study the short and medium-range structure for three different chemistries: 2KF-NaF, 2LiF-BeF2, and 3LiF-AlF3, with and without Cr solutes. The results show qualitative differences in salt structure and dynamics. While 2KF-NaF melts show short and medium range order that is highly dynamic, 2LiF-BeF2 and 3LiF-AlF3 are characterized by formation of long-lived molecular associates that organize into oligomer structures on larger length scales, consistent with thermodynamic models. It is shown that in these associate-forming systems, dissolved Cr ions can incorporate into and be solvated within this oligomer structure. Implications for corrosive processes of molten salts will be discussed.