Mercuride anions: synthesis, structural chemistry and chemical bonding in alkali metal mercuride oxides

汞是一种独特的元素，它的性质和丰富的结构化学都是如此。它的准稀有气体电子组态4f145d106s26p0产生了高贵的特征，由于f收缩和相对论效应导致轨道能量的移动而增强了这一特征。这导致了汞的一个特殊方面：高尚的品质与特别低的阴离子形成倾向的结合。在这一点上，汞不同于它的邻近元素铂、金、铊、铅和铋。这些元素中的大量阴离子是已知的，既有单原子阴离子，也有多原子团簇阴离子。越来越多的人怀疑汞也能形成类似的阴离子--电子构型使这一点变得非常令人难以置信。我们现在已经成功地用阴离子汞制备了第一个化合物。根据标准固态化学，化合物由Cs、Hg和O在低温(T&lt；300°C)下形成，该低温(T&lt；300°C)包含汞阴离子和氧化物阴离子以及双盐结构的铯阳离子。立方阴离子[Hg8]^6-可以在多种情况下发现，但也存在一个[Hg12]^6-阴离子，其形状为两个面凝聚的立方体。新的汞阴离子可以与其他金属阴离子进行比较，并与铊阴离子建立了密切的化学和结构关系。与金化物、铂、铅或铋的阴离子不同，硫化物和汞的阴离子不能用简单的电子计数规则来解释。为了理解形成、稳定性和几何结构，必须考虑相对论效应。这里介绍的第一批汞氧化物的制备、结构和光谱研究是硕士论文的成果，它们将在博士工作的框架内深化。这篇博士论文的撰写需要DFG的资助。我们将在这里展示汞氧化物提供了丰富的结构化学，并将发展成为具有有趣的化学和结构特征的化合物大家族。在更大类别晶体结构的基础上，将能够对汞离子中的化学键进行全面分析，从而能够更深入地了解相对论效应对固态化合物的化学键、结构形成和性质的作用。

Mercury is a unique element, regarding both its properties and its rich structural chemistry. Its quasi-noble-gas electron configuration 4f145d106s26p0 causes a noble character, enhanced by a shift of the orbital energies due to f-contraction and also relativistic effects. Thies leads to one of the special aspects of mercury: the combination of noble character with an especially low tendency toward formation of anions. In this, mercury differs from its neighbouring elements Pt, Au, Tl, Pb and Bi. A large number of anions from these elements are known, monoatomic ones as well as polyatomic cluster anions. It has multiply been doubted that mercury could also form analogous anions - the electron configuration renders this very implausible.We now have succeded in preparing the first compounds with anionic mercury. Compounds form from Cs, Hg and O at - with respect to standard solid state chemistry - low temperature (T < 300 °C) wich contain mercuride anions and oxide anions together with cesium cations in double salt-like structures. The cubic anion [Hg8]^6- can be found in multiple cases, but also a [Hg12]^6- anion with the shape of two face-condensed cubes is present. The novel mercuride anions can be compüared to other metalide anions, and a close chemical and structural relation to the thallide anions can be established. Thallide as well as mercuride anions cannot be explained by simple electron counting rules, in contrast to auride, platinide, plumbide or bismutide anions. In order to understand formation, stability and geometric structures relativistic effects have to be taken into account. The studies on preparation, structure and spectroscopy of the first mercuride oxides presented here are the results of a Master's thesis and they shall be deepened in the frame of a PhD work. Funding from DFG is requested to enable this PhD thesis. We will show here that mercuride oxides provide a rich structural chemistry and will develop into a large family of compounds with intriguing chemical and structural features. On the basis of a larger class of crystal structures a comprehensive analysis of the chemical bonding in the mercuride anions will be enabled, allowing for a deeper insight in the role of relativistic effects on chemical bonding, structure formation and properties of solid state compounds.