Theory

理论

• 批准号: 238350894
• 负责人: Professor Dr. Andreas Görling
• 金额: --
• 依托单位: Institut für Theoretische Physik
• 依托单位国家: 德国
• 项目类别: Research Units
• 财政年份: 2013
• 资助国家: 德国
• 起止时间: 2012-12-31 至 2022-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/238350894?language=en
• 关键词: Theory

In close collaboration with the other funCOS projects, funCOS 6 focuses on a comprehensive theoretical atomic-scale understanding of the adsorbate-substrate and adsorbate-adsorbate interactions of functionalized organic molecules on structured metal-oxide surfaces, with the aim to eventually enable a controlled formation of organic films with specific structural, electronic and optical properties. Means to alter the adsorbate-substrate interaction are the substitution of organic molecules with specific linker groups or the modification of the substrate, for instance via a surface hydroxylation. In this way, adsorption sites and geometries on pristine surfaces or at low-coordinated sites at nano-structured metal-oxide substrates may be influenced. The adsorbate-substrate interaction includes chemical reactions like the self-metallization of porphyrins. The adsorbate-adsorbate interaction, which hinges on the adsorbate-substrate interaction via the distance between adjacent adsorption sites, can be tuned via functional groups. The funCOS theory area pursues theoretical modeling of these topics based on density- functional theory supplemented by Van-der-Waals corrections and Hubbard-U approaches, ab initio molecular dynamic simulations, and additional high-level electronic structure methods, i.e. time-dependent density functional theory, many-body perturbation theory (GW/BSE), and wave- function-based methods. Investigations will take up the knowledge gained in the first funding period of funCOS on linker molecules, networks of smaller organic molecules, and metalation reactions of functionalized porphyrins. Metal adatoms in combination with functionalized organic molecules may open new opportunities to create 2D metal-organic networks. Modeling will predict which combinations of adatoms and linker groups are promising for the self-assembly of such networks. The metal-oxide substrate is a key element of structure formation and thus a topic of investigations regarding its electronic properties and low-coordinated sites such as surface defects, metal adatoms or hydroxyl groups. The surfaces of MgO, TiO2, and different cobalt oxides and corresponding thin oxide films on metals, specifically MgO/Ag(100), CoO(100)/Ir(100), and Co3O4(111)/Ir(100) will be investigated. In this respect, novel nanoparticle systems, like Mg(1-x)Co(x)O nanocrystals and MgO nanocube stacks, are of particular interest as they feature Co atoms at the surface, surfaces of different orientation and connecting elements as adsorption sites for functional molecules. Deposition of large organic molecules from solution is a very appealing, experimentally easy to handle alternative to the gas phase preparation. To take ab initio modeling beyond the surface science approach to the metal oxide/liquid interface is a huge step. The funCOS theory area will investigate interactions of liquids with metal oxides and chemical reactions at the liquid/oxide interface.

与FunCOS的其他项目密切合作，FunCOS 6专注于从理论上全面理解功能化有机分子在结构金属氧化物表面的吸附-衬底和吸附-吸附相互作用，目的是最终能够控制形成具有特定结构、电子和光学性质的有机薄膜。改变吸附物-底物相互作用的手段是用特定的连接基取代有机分子或对底物进行修饰，例如通过表面羟化。通过这种方式，可能会影响原始表面或纳米结构金属氧化物衬底上的低配位的吸附位置和几何形状。吸附-底物相互作用包括类似于卟啉自金属化的化学反应。吸附-吸附相互作用可以通过官能团进行调节，这种相互作用取决于通过相邻吸附位置之间的距离实现的吸附-底物相互作用。FunCOS理论领域基于密度泛函理论，辅以Van-der-Waals修正和Hubbard-U方法，从头算分子动力学模拟，以及附加的高级电子结构方法，即含时密度泛函理论、多体微扰理论(GW/BSE)和基于波函数的方法，对这些主题进行理论建模。调查将包括FunCOS第一个资助期在连接物分子、较小有机分子网络和官能化卟啉的金属化反应方面获得的知识。金属吸附原子与官能化有机分子的结合可能为建立2D金属-有机网络提供新的机会。建模将预测吸附原子和连接基的哪些组合有望实现此类网络的自组装。金属氧化物衬底是结构形成的关键元素，因此是研究其电子性质和低配位位置(如表面缺陷、金属原子或羟基)的一个主题。我们将研究氧化镁、二氧化钛和不同的钴氧化物以及相应的氧化膜在金属上的表面，特别是镁/银(100)、CoO(100)/Ir(100)和Co3O4(111)/Ir(100)。在这方面，新型纳米粒子系统，如Mg(1-x)Co(X)O纳米晶和MgO纳米立方体堆叠，特别令人感兴趣，因为它们的表面特征是Co原子，不同取向的表面和连接元素作为功能分子的吸附中心。从溶液中沉积大的有机分子是一种非常吸引人的、在实验上易于操作的替代气相制备的方法。对金属氧化物/液体界面进行超越表面科学方法的从头算模拟是一大步。FunCOS理论领域将研究液体与金属氧化物的相互作用以及液体/氧化物界面上的化学反应。