Mineral physics of icy planetary bodies

外太阳系包含大量富含冰的天体，大小从几公里到几千公里不等；后者包括木星的卫星木卫三和木卫四，以及土星的卫星土卫六，它们都比水星大。几十年来，人们已经认识到，这些大型冰体的“冰”部分将从它们的“脏雪球”增生前体继承额外的挥发性和非挥发性成分，并且在岩心分化期间也将经历大量的热液处理。其结果是，“冰”层将包含一系列水合物化合物，作为“造岩矿物”。然而，直到最近20年，实验和计算矿物物理方法才提供了工具来确定这些材料在压力和温度（0 < P < 5 GPa, 100 < T < 400 K）的相关条件下的行为。这种工作对于确保结构和演化模型的准确基础是必不可少的，而结构和演化模型又提供了解释远程和原位行星探测的观测数据的手段。本项目旨在解决高压水合物矿物结构和性质方面长期存在的问题，合成和回收子午线（MgSO4.11H2O）、芒硝（Na2SO4.10H2O）、二水合氨（NH3.2H2O）和各种硫酸水合物（H2SO4.nH2O）等材料的高磷多晶或解解产物。

The outer solar system contains a large number of ice-rich objects, ranging in size from a few km to a few thousand km across; the latter includes the Jovian satellites Ganymede and Callisto and the Saturnian moon Titan, each of which are larger than the planet Mercury. It has been recognised for many decades that the 'ice' portion of these large icy bodies will have inherited additional volatile and non-volatile constituents from their 'dirty snowball' accretionary precursors and will also have undergone substantial hydrothermal processing during core differentiation. The result of this is that the 'ice' layers will contain a range of hydrate compounds as 'rock-forming minerals'. However, it is only in the last 20 years that experimental and computational mineral physics methods have provided the tools to determine the behaviour of these materials under the relevant conditions of pressure and temperature (0 < P < 5 GPa, 100 < T < 400 K). Such work is essential to ensure an accurate basis for structural and evolutionary modelling, which in turn provides the means of interpreting observational data from remote and in situ planetary exploration.The aim of this studentship is to address long-standing problems in the structure and properties of high-pressure hydrate minerals, synthesising and recovering high-P polymorphs or dissociation products of materials such as meridianiite (MgSO4.11H2O), mirabilite (Na2SO4.10H2O), ammonia dihydrate (NH3.2H2O) and various sulfuric acid hydrates (H2SO4.nH2O).