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

就其性质和丰富的结构化学而言，汞是一种独特的元素。它的准惰性气体电子构型4f145d106s26p0造成了惰性，由于f收缩和相对论效应引起的轨道能量的移动而增强了惰性。这导致了汞的一个特殊方面：高贵的性质与特别低的阴离子形成倾向的结合。在这一点上，汞与邻近的元素Pt、Au、Tl、Pb和Bi不同。这些元素的大量阴离子是已知的，有单原子阴离子，也有多原子簇阴离子。水银也能形成类似的阴离子的说法一直受到质疑，因为电子的结构使这种说法非常不可信。我们现在已经成功地制备了第一批阴离子汞化合物。化合物由Cs， Hg和O形成-相对于标准固态化学-低温（T < 300°C），其中含有汞阴离子和氧化物阴离子以及双盐状结构的铯阳离子。立方阴离子[Hg8]^6-可以在多种情况下发现，但也存在两个面凝聚立方体形状的[Hg12]^6-阴离子。新型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、铂、铅或铋阴离子不同，铊和汞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。本文介绍的第一批汞氧化物的制备、结构和光谱学研究是硕士论文的成果，应在博士论文的框架内进一步深化。请DFG提供资金以完成这篇博士论文。我们将在这里展示汞氧化物提供了丰富的结构化学，并将发展成为一个具有有趣的化学和结构特征的大家族化合物。在更大类晶体结构的基础上，对汞阴离子中的化学键进行全面分析将成为可能，从而更深入地了解相对论对化学键、固体化合物的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.