FA: Modelling the solubility of inorganic compounds under hydrothermal and ammonothermal conditions using reduced fluid properties

4. Dezember 2025

Maitri Bharatbhai Savani –

This work examines the solubility of gallium nitride (GaN) in supercritical ammonia to understand its behavior under ammonothermal growth conditions. A systematic evaluation and comparison of thermodynamic and empirical models was conducted. Results demonstrate that density-based models (Chrastil, Mendez-Santiago-Teja) correlate GaN solubility with significantly higher accuracy than temperature-based approaches (van’t Hoff, Apelblat), highlighting that solvent density, rather than temperature alone, is the governing variable for correlating solubility across the investigated supercritical regime. Beyond this comparative analysis, a reducedproperty framework was applied to compare GaN solubility in supercritical ammonia with ZnO solubility in hydrothermal water systems. When expressed in terms of reduced density, the datasets show similar overall trends, indicating that solvent density is a key correlating variable across different high-pressure solvent environments. However, the alignment is not universal; mineralizer chemistry introduces systematic variations, and more datasets are required to evaluate the generality of this observation.

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