Speciation of rare earth elements in hydrothermal systems

本项目旨在利用分子模拟方法对热液流体中稀土元素形态进行研究和定量。从模拟中导出了物种的稳定常数。它们是热液成矿系统热力学建模的重要参数。到目前为止，这些参数在很大程度上是不受约束的，或者是从具有很大不确定性的低温实验中推断出来的。物种形成模型用于预测在何种条件下稀土元素在热液系统中被动员（和浓缩）。在这个项目中，我们将开发基于机器学习算法的新的交互潜力。由于它们的高效率和准确性，新势将越来越多地用于分子动力学模拟，至少部分取代迄今为止使用的从头算方法。研究的重点是重稀土元素和轻稀土元素的代表元素钇和镧。对于络合物的形成，我们将集中讨论混合氯化物/氢氧化氟配体以及硫酸盐和碳酸盐配体。

This project is aimed at the investigation and quantification of rare earth element speciation in hydrothermal fluids using molecular modeling approaches. From the simulations species stability constants are derived. They are important parameters for thermodynamic modeling of hydrothermal ore-forming systems. So far, these parameters are largely unconstraint or they have been extrapolated from low temperature experiments with large uncertainty. The speciation models are used to predict under which conditions rare earth elements are mobilized (and concentrated) in hydrothermal systems. Within the project we will develop new interaction potentials based machine-learning algorithms. Due to their high efficiency and accuracy the new potentials will be used increasingly in molecular dynamics simulations and at least partially replace ab initio methods used to far. The focus of the investigation will be on the elements yttrium and lanthanum as representatives of the heavy and the light rare earth elements. For the complex formation we will concentrate on mixed chloride/fluoride-hydroxide ligands as well as on sulfate and carbonate ligands.