Excited State Properties and Spectroscopy of Semiconductor Nanoparticles

基于碳和硅的分子团簇是非常有趣的纳米材料，在分子电子学、材料科学、医学和纳米光子学中具有潜在的应用。在这里，我们的目标是在理论上确定的Si和C为基础的半导体粒子光激发后的电子特性：他们的光谱特征，动态命运，和“调谐”。使用第一性原理电子结构理论和时间相关函数技术，振动分辨吸收和发射将被确定。一个特别的焦点是共振拉曼光谱。相关函数方法是非常有效的，开辟了一条道路复杂的分子结构的理论处理。自旋轨道和其他非绝热耦合及其对光谱和激发态寿命的影响也很有趣。该理论将被应用于原始的，但主要是改性的金刚石，包括C/Si杂化物。对于这些物种，我们希望设计它们的电子特性，例如，荧光行为，通过“电子共混”，并提供基本的理解的基础physics。

Molecular clusters based on carbon and silicon are highly interesting nanomaterials for potential applications in molecular electronics, materials science, medicine, and nano-photonics. Here we aim at the theoretical determination of electronic properties of Si- and C-based semiconductor particles after photoexcitation: their spectroscopic signatures, dynamical fate, and “tuning”. Using first principles electronic structure theory and time-dependent correlation function techniques, vibronically resolved absorption and emission will be determined. A special focus is on resonance Raman spectra. Correlation function approaches are highly efficient, opening a way towards the theoretical treatment of complex molecular structures. The inclusion of spin-orbit and other non-adiabatic couplings and their influence on spectra and excited state lifetimes is also of interest. The theory will be applied to pristine, mostly however to modified diamondoids including C/Si hybrids. For these species, we wish to design their electronic properties, e.g., fluorescence behaviour, by “electronic blending”, and provide fundamental understanding of the underlying photophysics.