PChem Seminar – Shinhyo Bang

About the event

Speaker: Shinhyo Bang

Group: Dr. Xiaofeng Guo

Title: Thermodynamics of Actinide-Bearing Zircon

Abstract:

The thermodynamics of zircon-structured silicates are profoundly influenced by both impurity incorporation and external pressure.

In the first part of this talk, I will present an empirical model describing the pressure-induced phase transition in a mixed actinide system (uranothorite), emphasizing the pivotal role of mixing enthalpy in controlling phase stability.

In the second part, I will discuss our recent investigation into the solubility limit of uranium in zircon (chernobylite), explaining why chernobylite cannot be synthesized beyond a certain uranium concentration. This limitation can be empirically rationalized by considering the mixing behavior of U and Zr polyhedra.

Far from being an abstract construct, the polyhedron serves as a fundamental unit in crystal chemistry, one that captures the structural and energetic essence of a material. I will conclude by extending this polyhedral perspective to uranium-doped yttrium aluminum garnet (YAG), demonstrating its broader relevance for understanding defect accommodation and stability in complex oxide systems.