Modelling Cluster Structures and Properties at Different Length Scales

发现了一种新的基于类金刚烷团簇材料的宽带白色发光材料。这种材料与廉价、低功率的连续波红外激光二极管相结合，有可能用于高亮度应用。第一个调查团簇材料[（StySn）4S6]由锡硫化物为基础的金刚烷类的核心饱和与有机苯乙烯配体。具有改性金刚烷核心组合物和不同有机配体的簇的调查表明，需要在宏观结构中的无序产生白色光。此外，另一个非线性光学效应，即二次谐波产生的基本激光，被发现的集群，不显示白色光的产生。最近的研究表明，需要了解团簇材料的结构和电子特性以及潜在的非线性光学效应，以设计和微调团簇材料所需的性能。这个理论研究项目将侧重于计算和模拟单个团簇的几何结构，直到固态材料和相关的电子和振动特性。因此，将考虑簇核心和有机配体的许多变化。该项目将与C2（Sanna）的理论项目密切合作，该项目侧重于非线性光学效应的建模和研究组的所有实验组。对单个团簇和小团簇聚集体的系统研究将有助于确定产生白色光或二次谐波的团簇的结构和性质的趋势。基于对团簇相互作用的基本结构特征的理解，类无定形固态团簇结构的建模将有助于理解团簇材料中的短程和长程有序及其操纵。该研究将回答的问题，如何集群的相互作用可以影响集群的组成。在彼此连接的不同长度尺度下的簇材料的计算将允许有益于优化所需非线性光学效应的结构和性质相关的见解。

A new spectrally broad band white light emitter based on adamantane-like cluster material has been discovered. This material in combination with cheap, low-power continuous-wave infrared laser diodes has the potential to be used in high-brilliance applications. The first investigated cluster material [(StySn)4S6] consists of a tin-sulfide-based adamantane-like core saturated with organic styrene ligands. Investigations of clusters with modified adamantane core composition and different organic ligands suggest that a disorder in the macroscopic structure is required to generate white light. Furthermore, another nonlinear optical effect, namely the second harmonic generation of the fundamental laser light, was found for clusters that show no white light generation. The recent studies demonstrate the need to understand the structural and electronic features of the cluster material as well as the underlying nonlinear optical effects in order to design and fine-tuning cluster materials to the desired properties. This theoretical research project will focus on the calculation and modelling of the geometric structures of single clusters up to solid state material and related electronic and vibrational properties. Therefore, numerous variations of the cluster core and the organic ligands will be considered. The project will closely collaborate with the theoretical project of C2 (Sanna) which focuses on the modelling of the nonlinear optical effects and all experimental groups of the research group. The systematic study of single clusters and small cluster agglomerates will allow to identify trends in structure and properties of white light or second harmonic generating clusters. Based on the understanding of the fundamental structural features of the cluster interaction, modeling of amorphous-like solid state cluster structures will contribute to the understanding of short- and long-range order in the cluster material as well as its manipulation. The study will answer the question how the cluster interaction can be influenced by cluster composition. The calculation of the cluster material at different length scales connected to each other will allow structural and property-related insights beneficial to an optimization for desired nonlinear optical effects.