A systematic exploration Method for the Development of metastable Metal Halides by Thermal Detection

该项目涉及一种新方法的开发和实际应用，该方法允许在一次测量中检测给定系统的整个系列金属卤化物化合物。按照一般程序，富含卤化物的金属卤化物(如WCl6)在逐级加热下与还原剂(如金属粉末)相继反应。由于存在足够数量的金属粉末并形成相应的金属卤化物，反应产物(例如在M-W-Cl体系中)是在随着金属含量的增加和卤化物含量的减少而产生的浓度梯度条件下依次形成的。对相应的反应步骤进行了热效应(DTA或DSC)监测，并用X射线衍射仪对产物进行了表征。将这种方法应用于卤化物体系，可以指定生成反应，检测生成热，以及大多数化合物可以被认为是亚稳态的化合物的表征。将对选定的化合物进行性质研究(例如，磁学、电学或光学)。这些研究的结果有望回答这样一个问题，即这样的优化方法是否能够用于其他系列的亚稳态化合物的研究。

This project deals with the development and practical application of a new method that allows the detection of an entire series of metal-halide compounds of a given system within one measurement. Following a general procedure, a halide-rich metal halide (e.g. WCl6) reacts successively with a reduction agent (e.g. metal powder) under progressive heating. Due to the presence of a sufficient amount of metal powder and the formation of a corresponding metal halide, the reaction products (e.g. in the M-W-Cl system) are successively formed under condition of a concentration gradient with increasing amount of metal and decreasing amount of halide. Corresponding reaction steps are monitored as thermal (DTA or DSC) effects and products are characterized by XRD. The application of this method to halide systems allows an assignment of formation reactions, the detection of formation heats, and characterizations of compounds of which the majority can be considered as metastable. Property studies (e.g. magnetic, electrical, or optical) will be performed for selected compounds.Results of these studies are expected to answer the question whether an optimized method like this is capable for investigations of other series of metastable solid state compounds.