Amalgams of less noble metals as model systems for polar intermetallic phases

低贵金属的汞齐作为极性金属间相的模型系统

• 批准号: 429690805
• 负责人: Privatdozent Dr. Constantin Hoch
• 金额: --
• 依托单位: Department Chemie
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2019
• 资助国家: 德国
• 起止时间: 2018-12-31 至 2022-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/429690805?language=en
• 关键词: Amalgams; less; noble; metals; model

Polar intermetallic phases are metallic compounds in which electric, magnetic or Coulombic dipoles from electronegativity differences are in interplay with the conduction electrons. They are the topic of intensive studies because this interplay leads to combinations of at the first glance irreconcilable properties, such as e.g. ferroelectricity and metallic conductivity in one material. The impact of polar intermetallic phases is porven by the increasing number of studies and first applications, e.g. in modern data storage devices. The underlying principles necessary for a targetted creation of new properties and new property combinations still aren't understood. Studying appropriate model systems may help a lot in systematically revealing the relevant structure property relations in polar intermetallic phases. Amalgams of the less noble metals have proven suitable as model systems over the last years, especially the mercury-richest members of this class of intermetallic compounds.The number of well-studied compunds in this fied still is too small as to give a clear picture over the general trends and rules. This project therefore deals with synthesis and structural and physical characterisation of new amalgams of less noble metals. New binaries, such as beryllium amalgams, as well as ternary amalgams with two different less noble metals shall be targetted in the first systematic study on Hg-rich amalgams. Chemical synthesis of gam-scaled samples and of single crystals for structural elucidation are the base for comprehensive characterisations by measurement of electric conductivity, susceptibility, as well as thermoanalytical and thermoelectrical behaviour. They will be combined with quantum-chemical calculations of the electronic structure and with NMR-spectroscopic determination of the Knight shift. This project is meant to increase knowledge on the interplay of conduction electrons with internal dipole moments in a metallic compound, in order to enable purposeful synthesis of polar intermetallic phases with combinations of properties suitable for application in new electronic materials and devices. Our group and our coworkers have shown with a number of preliminary studies on this topic to be capable of auspiciously conducting this project.

极性金属间相是金属化合物，其中电负性差异产生的电、磁或库仑偶极子与传导电子相互作用。它们是深入研究的主题，因为这种相互作用导致乍一看不可调和的属性的组合，例如一种材料中的铁电性和金属电导率。越来越多的研究和首次应用证明了极性金属间相的影响，例如在现代数据存储设备中。有针对性地创建新属性和新属性组合所需的基本原则仍不清楚。研究合适的模型系统可能有助于系统地揭示极性金属间相的相关结构性质关系。在过去的几年里，较低贵金属的汞齐已被证明适合作为模型系统，尤其是此类金属间化合物中汞含量最高的成员。该领域经过充分研究的化合物数量仍然太少，无法给出清晰的图片总体趋势和规则。因此，该项目涉及新型低贵金属汞合金的合成、结构和物理表征。新的二元汞齐，例如铍汞齐，以及含有两种不同的次贵金属的三元汞齐，应成为第一个富含汞汞齐的系统研究的目标。用于结构阐明的 gam 级样品和单晶的化学合成是通过测量电导率、磁化率以及热分析和热电行为进行综合表征的基础。它们将与电子结构的量子化学计算和奈特位移的核磁共振波谱测定相结合。该项目旨在增加对金属化合物中传导电子与内部偶极矩相互作用的了解，以便有目的地合成具有适合新电子材料和器件应用的性能组合的极性金属间相。我们的团队和我们的同事对此主题进行了多项初步研究，表明有能力顺利开展该项目。