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，无论是其性质还是其丰富的结构化学，其准惰性气体电子构型 4f145d106s26p0 都具有高贵的特性，并且由于 f 收缩和相对论效应而导致轨道能量的变化而增强。汞的一个特殊方面是：兼具高贵的特性和极低的阴离子形成倾向，在这一点上，汞不同于其邻近元素 Pt， Au、Tl、Pb 和 Bi 是已知的大量阴离子，包括单原子阴离子和多原子簇阴离子，人们多次怀疑汞也可以形成类似的阴离子 - 电子构型使这一点变得非常难以置信。现在已成功制备出第一种由 Cs、Hg 和 O 在低温（T < 300）条件下形成的阴离子汞化合物。 °C），其中包含汞阴离子和氧化物阴离子以及双盐状结构中的铯阳离子 立方阴离子 [Hg8]^6- 可以在多种情况下找到，但也可以找到具有以下形状的 [Hg12]^6- 阴离子。存在两个面稠合立方体的新型汞化物阴离子可以与其他金属化物阴离子进行比较，并且可以与卤化物阴离子有密切的化学和结构关系。与金化物、铂化物、铅化物或铋化物阴离子相比，铊化物和汞化物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，在制备时必须考虑相对论效应。这里介绍的第一个汞氧化物的结构和光谱是硕士论文的结果，它们将在 DFG 资助的博士工作框架中得到深化。我们将在此展示汞氧化物提供丰富的结构化学，并将在对更大类别的晶体结构进行全面分析的基础上发展成为具有有趣化学和结构特征的一大类化合物。汞阴离子中的化学键将被启用，从而可以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。