Double salts with a multifunctional character made from Zintl phases and oxo- as well as halogeno-metalates

本研究项目的目的是通过合成固态化学，通过在分子离子水平上结合两种无机成分，开发新功能材料的基础化合物。重点是三角形，多阴离子锗和锡簇，包括9个原子，这是在与第二种类型的阴离子，如草酸盐和金属卤化物阴离子的组合形成新的，混合半导体固态材料（复盐）。由于它们的相互结构可调性，碱金属Zintl相和碱金属氧化物或金属卤化物的组合为新的多组分杂化材料的产生和设计提供了许多可能性。由于复盐可以出现可变的组成，这种化合物类具有可调带隙的潜力。这类新材料在光电子学中具有应用潜力，原则上也可作为水裂解催化剂。第一步，基于少数已知的代表性化合物，系统地开发了复盐的合成方案，并将其应用于各种其他组合。通过X射线衍射和拉曼光谱对新化合物的结构进行了表征。基本的电子性能，如带隙或磁性，氧化态的构成元素，建议可能的电荷转移之间的单元，实验确定。利用量子化学计算方法，一方面计算了电子结构和带隙。另一方面，稳定的，新的，未知的候选人与杂交性状的基础上确定的结构关系和测试方面的热力学稳定性，使用理论方法。在进一步的步骤中，使用开发的合成方案特异性地合成所选择的候选物。具体地，在此处申请的项目中，制备了混合化合物，其含有聚阴离子[Ge 9] 4-、[Sn 9] 4-和[M@Sn 9] x-作为组分1，以及[MO 4] x-的金属氧化物或金属卤化物阴离子。（M =过渡金属）或四面体配位的卤化物（例如[SnBr 4] 2-、[PbBr 4] 2-、[MX 4] x-; X =卤素）或[MX 6] x-（M = Sn、Pb）类型的卤化物作为组分2。这两种成分的结构单元被称为碱金属化合物，然而，在这里首次系统地开发了它们的组合。组分2如今已经用于金属青铜和太阳能电池。该组合使得组件的构建单元之间的电荷转移过程和更好的可调谐带隙成为可能。

This research project aims for the development of fundamental compounds for new functional materials by means of synthetic solid-state chemistry through the combination of two inorganic components at the molecular ionic level. The focus is on deltahedral, polyanionic germanium and tin clusters comprising nine atoms, that are in combination with a second type of anion such as oxometalates and metal-halide anions form new, hybrid semiconducting solid state materials (double salts). Due to their mutual structural tunability, the combination of both alkali-metal Zintl phases and alkali-metal metal-oxides or metal-halides offers numerous possibilities for the generation and design of new multi-component hybrid materials. Since double salts can appear with variable composition, this compound class has the potential for tunable band gaps. The new material class has application potential in optoelectronics and, in principle, also as a water splitting catalyst.In a first step, synthesis protocols for double salts are systematically developed based on the few known representatives and are applied to various other combinations. The new compounds are structurally characterized by means of X-ray diffraction methods and Raman spectroscopy. Basic electronic properties such as band gaps or magnetic properties, oxidation states of the constituting elements that suggest a possible charge transfer between the units, are determined experimentally. Using quantum chemical calculations, on the one hand, the electronic structures and band gaps are calculated. On the other hand, stable, new, unknown candidates with hybrid character are identified on the basis of structural relationships and tested with regard to thermodynamic stability using theoretical methods. In a further step, selected candidates are specifically synthesized using the synthesis protocols developed. Specifically, in the project applied for here, hybrid compounds are produced which contain the polyanions [Ge9]4–, [Sn9]4– and [M@Sn9] x– as component 1 and metal-oxide or metal-halide anions of the [MO4]x– (M = transition metal) or tetrahedrally coordinated halides (e.g. [SnBr4]2–, [PbBr4]2–, [MX4]x-; X = halogen) or halides of the type [MX6]x- (M = Sn, Pb) as component 2. The structural units of both components are known as alkali-metal compounds, however in combination they are systematically developed here for the first time. Component 2 is already used today in metallic bronzes and in solar cells. The combination enables charge-transfer processes between the building units of the components and better tunable band gaps.