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

汞阴离子：碱金属汞氧化物中的合成、结构化学和化学键合

• 批准号: 513247541
• 负责人: Privatdozent Dr. Constantin Hoch
• 金额: --
• 依托单位: New Technologies - Research Centre
• 依托单位国家: 德国
• 项目类别: Research Grants
• 资助国家: 德国
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/513247541?language=en
• 关键词: Mercuride; anions; synthesis; structural; chemistry

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.

汞是一种独特的元素，就其性质和丰富的结构化学而言。它的准惰性气体电子组态4f 145 d106 s26 p0导致了一个高贵的特性，由于f-收缩和相对论效应，轨道能量的移动增强了这种特性。这导致了汞的一个特殊方面：高贵的特性与形成阴离子的特别低的倾向相结合。在这一点上，汞不同于其邻近元素Pt、Au、Tl、Pb和Bi。已知这些元素的大量阴离子，单原子阴离子以及多原子簇阴离子。汞也能形成类似的阴离子，这一点曾受到多次怀疑--电子构型使这一点非常不可信。我们现在已经成功地制备出了第一批阴离子汞化合物。在低温（T < 300 °C）下，由铯、汞和氧形成的化合物含有汞化物阴离子和氧化物阴离子，以及铯阳离子，形成类似复盐的结构。立方晶系阴离子[Hg 8]^6-可以在多种情况下被发现，但也存在两个面凝聚立方体形状的[Hg 12]^6-阴离子。这些新的汞阴离子可以与其它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、铅或铋的阴离子不同，铊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。 本文介绍的第一批氧化汞的制备、结构和光谱学研究是硕士论文的结果，将在博士论文的框架内进一步深化。从DFG的资金要求，使这篇博士论文。我们将在这里展示，汞化物氧化物提供了丰富的结构化学，并将发展成为一个大家族的化合物与有趣的化学和结构特征。在更大类别的晶体结构的基础上，将能够对汞化物阴离子中的化学键合进行全面分析，从而更深入地了解相对论效应对化学键合、结构形成和固态化合物性质的作用。