Quantum chemical and quantum dynamical studies of the photocatalytic water splitting on titanium dioxide surfaces

在无机材料光催化水分解（人工光合作用）这一主题上，一个精心设计的发展新概念和新技术的策略是基于对潜在基本过程的详细的，即原子的理解。当前研究计划的具体目标包括尽可能准确地模拟理想、含缺陷和氮掺杂（金红石和锐钛矿）钛- tio2表面的光催化水分解。这些表面代表了足够简单的模型系统，允许通过现代量子化学和量子动力学方法研究相关的光催化过程，而不依赖于实验数据。该从头算方法基于涉及H2O/TiO2(110)-体系光催化水分解的电子基态和电子激发态的嵌入式簇模型，并追求超越电流密度泛函理论（DFT）的精确量子化学方法，即CASSCF和CASPT-2。这些方法可以计算精确的电子基态和电子激发态的五维势能面，它们构成了随机波包计算框架内精确量子动力学模拟的基础，为与实验结果直接比较人工光催化机制的基本见解铺平了道路。

A well-designed strategy for the development of new concepts and technologies on the subject of photocatalytic water splitting by inorganic materials (artificial photosynthesis) is based on a detailed, i.e. atomistic understanding of the underlying elementary processes. The specific goal of the current research proposal consists of the effort to simulate the photocatalytic water splitting on ideal, defect containing, and nitrogen-doped surfaces of (rutile and anatase) titania-TiO2 as accurately as possible. These surfaces represent sufficiently simple model systems which allow for the study of the relevant photocatalytic processes by modern quantum chemical and quantum dynamical approaches without relying on experimental data. This ab initio approach is based on embedded cluster models of the electronic ground state and electronically excited states involved in photocatalytic water splitting of the H2O/TiO2(110)-system and pursues accurate quantum chemical methodology beyond current density functional theory (DFT), i.e. CASSCF and CASPT-2. These methods allow for the calculation of accurate, five-dimensional potential energy surfaces of the electronic ground state and electronically excited states which form the basis for exact quantum dynamical simulations within the framework of stochastic wave packet calculations paving the way for fundamental insight into the mechanism of artificial photocatalysis in direct comparison with experimental results.