含孤对电子非对称单元新型硫代硼酸盐类红外材料探索合成

项目名称： 含孤对电子非对称单元新型硫代硼酸盐类红外材料探索合成

项目编号： No.51302100

项目类型： 青年科学基金项目

立项/批准年度： 2014

项目学科： 一般工业技术

项目作者： 耿磊

作者单位： 淮北师范大学

项目金额： 25万元

中文摘要： 硼酸盐是一类重要的非线性光学晶体材料，在紫外、可见光波段应用广泛。然而由于强的硼-氧共价键引起的多声子吸收，该类化合物的红外截止边通常处在近红外波段附近。本研究课题基于对晶体结构-光学性能关系和阴离子基团理论的理解，结合分子工程学中微观结构基元设计与调控的方法，提出将硼酸盐中半径较小的氧阴离子用半径较大的硫阴离子替换，引入偶极矩较大的含孤对电子非对称结构单元，通过无水、无氧条件下真空封管高温固相合成的途径，设计合成具有良好中远红外透过性能的新型非线性光学晶体，测定化合物的晶体结构、紫外/可见/近红外吸收光谱、热稳定性能等，并对化合物的电子能带结构、态密度及光学性质进行理论计算和分析，确定晶体结构中对材料的光学性能起关键作用的结构敏感基元，并对其进行化学修饰或结构调控，以期实现对硫代硼酸盐体系化合物的合理设计和可控合成，为新型中远红外非线性光学晶体材料的研究开发提供科学依据。

中文关键词： 孤对电子；水热合成；单晶结构；光学晶体；

英文摘要： Borates are an important kind of photoelectric functional materials, and have wide applications in the fields of nonlinear optics, laser materials, laser spectroscopy, communications, medical applications, etc. However, the strong B-O covalent bonds and hence the multi-phonon absorption make their IR cut-off edges are usually located around near-IR region. This project is mainly based on the relationships between the crystal structures and their optical properties.And together with the method of design and control of microstropic structure in the view of the molecular engineering, we proposed the thought of substituting the element of sulfur for oxygen in the borates, coorparating with lone-pairs asymmetric units with large dipole moments. Using the high temperature solid-state synthesis route under water- and oxygen-free conditions in evacuated sealed tubes we attempted to synthesize new types of photoelectronic functional thioborate compounds with excellent mid- and far-IR optical transparency, determine the crystal structures, and measure the UV/Vis/NIR absorption spectra and the thermal stability of the compounds synthesized. We will perform the calculations of the electronic structure, density of states, and optical properties, and find the key structural units which are sensitive to their optical propertie

英文关键词： lone-paire electrons；hydrothemal synthesis；single crystal structure；optical crystal；