基质—稀土离子能量传递理论及第一性原理计算

项目名称： 基质—稀土离子能量传递理论及第一性原理计算

项目编号： No.11274299

项目类型： 面上项目

立项/批准年度： 2013

项目学科： 数理科学和化学

项目作者： 段昌奎

作者单位： 中国科学技术大学

项目金额： 80万元

中文摘要： 稀土发光材料的应用涉及信息、能源、生物医学和高能粒子探测等方方面面。基质对稀土离子(4f)^N组态内跃迁的敏化和(4f)^(N-1)5d-(4f)^N组态间跃迁性能的调控，是实现掺稀土发光材料各种功能的关键手段。宽禁带半导体掺稀土离子发光材料和绝缘体掺稀土离子闪烁体作为节能环保照明、光信息处理和生物医学影像材料是重要研究对象，决定其性能的共同关键是实现能量从基质到发光中心的有效传递。拟：1）考虑各种关键因素，如：以稀土离子电荷迁移态和空穴束缚态作为中转状态的能量传递过程和这些能量状态作为虚中间态的直接传递过程等，给出从基质的离域性激发态向稀土离子发光中心多电子耦合局域化能态的能量传递的具有一定普适性的微观理论； 2）实现和第一性原理相结合的计算方法和软件代码； 3）把理论结果和计算方法用于基于基质进行性能调节的稀土体系的性能分析与预言，为节能材料、探测材料和新能源材料的探索提供理论支持。

中文关键词： 稀土离子光谱理论；能量传递；固体激发态动力学；第一性原理计算；稀土光功能材料

英文摘要： The applications of lanthanide luminescent materials cover the disciplines of information technology, materials for renewable energy, biomedical science and detection of cosmic radiations. The sensitization of emission due to transitions between two states of (4f)^N electron configuration and the manipulation of the optical properties related to (4f)^(N-1)5d-(4f)^N transitions are key strategies in realizing various functions of lanthanide luminescent materials. Lanthanide doped wide-bandgap semiconductors and inorganic insulator scintillators are two important types of materials under intensive research, for their applications in energy-saving lighting, information manupilation and transmission, and biomedical imaging. The common factor crucial for both types of luminescent materials is the efficiency of energy transfer from the host to luminescent centers. The objectives are: 1) to derive a general microscopic energy transfer theory by including all the key contributions, such as the energy transfer processes via ligand-metal charge transfer states and trapped hole states as actually intermediate steps, and direct energy transfer process with these states as virtual intermediate states; 2) to develop the method and computer codes to calculate the energy transfer rates using the output of ab initio calculatio

英文关键词： Rare-earth spectroscopy；Energy transfer；Excited-state dynamics in solids；First-principle calculations；Rare-earth functional materials