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题名	新型硼酸盐和磷酸盐化合物的合成、结构和性能研究
作者	曹箭
学位类别	硕士
答辩日期	2012-05
授予单位	中国科学院研究生院
授予地点	北京
导师	潘世烈
关键词	SrCdB2O5 PbCaB2O5 LiK3P2O7 晶体材料 晶体结构
学位专业	材料物理与化学
中文摘要	近十年来，由于以通信和信息为基础的社会变革的不断深入，使得作为重要的信息材料之一的晶体材料得到了快速的发展，并在信息、科研、医疗、国防等领域有重要的应用，例如可以制成调制、开关、存贮等各种进行光信息处理的元器件。 本论文主要合成了两种新型的硼酸盐晶体SrCdB2O5、PbCaB2O5和一种新型的磷酸盐晶体LiK3P2O7，并对它们的光学以及热学性能进行了测试，并通过密度泛函(DFT)平面波赝势方法分析了其电子结构和光学性能。 1. SrCdB2O5化合物的合成、晶体生长和性质研究。 本实验采用高温熔液法，通过自发结晶获得了SrCdB2O5晶体。SrCdB2O5 是 SrO-CdO-B2O3体系中首次发现的化合物。SrCdB2O5晶体属于正交晶系，空间群为 Pbca (No. 61)，晶胞参数：a = 12.010(4) Å，b = 5.795(2) Å，c = 12.677(4) Å，Z = 8。 SrCdB2O5 的结构由独立的 B2O5 基团，CdO6 多面体和 SrO9 多面体连接形成。红外光谱则证明了 SrCdB2O5 晶体阴离子基团有 BO3 基团。并且对 SrCdB2O5 晶体进行了理论计算，结果表明SrCdB2O5晶体的带隙宽度为Eg=3.471 eV，该晶体光学效应主要是由导带和价带结构中的 B-O 基团引起的。 2. PbCaB2O5化合物的合成、晶体生长和性质研究。 首次通过高温熔液法合成了一种新型硼酸铅钙化合物PbCaB2O5。PbCaB2O5晶体属于三斜晶系，空间群P (No. 2)，晶胞参数：a = 3.6736(6) Å，b = 6.5363(11) Å，c = 9.7585(17) Å，α= 100.504(2)°，β = 90.752(2)°，γ = 91.627(2)°，Z = 2。PbCaB2O5 的结构由独立的B2O5基团，PbO5多面体和Pb/CaO7多面体连接形成。红外光谱证明PbCaB2O5晶体中阴离子基团存在BO3基团。 3. LiK3P2O7化合物的合成、晶体生长和性质研究。 首次合成了一种新型磷酸盐晶体LiK3P2O7。LiK3P2O7晶体属于正交晶系，空间群C2221 (No. 20)，晶胞参数为a = 6.0373(14)Å，b = 9.339(2)Å, c = 13.292(3)Å，Z = 4，V = 749.4(3) Å3。两个PO4四面体通过O(4)相连，形成 [P2O7]4- 基团，每一个 [P2O7]4- 基团通过共享O连接三个LiO4多面体，同时，每一个LiO4多面体都与相邻的三个 [P2O7]4- 基团共享四个顶点，形成∞[LiP2O7]3- 层，∞[LiP2O7]3- 层之间通过K(1) 和K(2) 相连，形成三维网络结构。同时还对该化合物进行了热学性能，红外光谱和紫外漫反射光谱的测试，能带计算表明LiK3P2O7晶体的带隙宽度为Eg= 4.559 eV。
英文摘要	In recent ten years, due to the continuous development of information technology, the crystal material as one of the important information of material acquired the rapid development. Moreover, it has played an increasingly important role in the field of high technology. In our study, two novel borates SrCdB2O5 and PbCaB2O5 and one novel phosphate LiK3P2O7 have been prepared by solid-state reactions. The spectrum properties, thermal analysis and theoretical calculations have been measured. 1. The synthesis, crystal growth and properties of SrCdB2O5 Single crystals of SrCdB2O5 were grown by the spontaneous crystallization using PbO-H3BO3 as the flux. SrCdB2O5 has been found in the SrO-CdO-B2O3 system for the first time. SrCdB2O5 crystallizes in the orthorhombic system, space group Pbca with unit-cell parameters a = 12.010(4) Å, b = 5.795(2) Å, c = 12.677(4) Å, Z = 8. The new structure contains an infinite three-dimensional matrix that is built from B2O5 units, CdO6 and SrO9 polyhedra. Spectrum properties measurements show only BO3 group in the SrCdB2O5. The theoretical calculations prove that the linear optical effects of SrCdB2O5 are primarily due to B-O groups from the structures of valence band and conduction band. The calculated band structures and the density of states of the compound suggests that the indirect gap is 3.471 eV. 2. The synthesis, crystal growth and properties of PbCaB2O5 A new lead calcium borate, PbCaB2O5, has been synthesized by the spontaneous crystallization using PbO-H3BO3 as the flux. PbCaB2O5 crystallizes in the triclinic space group P = 3.6736(6) Å, b = 6.5363(11) Å, c = 9.7585(17) Å, α= 100.504(2)°, β = 90.752(2)°, γ = 91.627(2)°, and Z=2. The crystal structure consists of isolated B2O5 units, PbO5 and Pb/CaO7 polyhedra. Spectrum properties measurement shows only BO3 group in PbCaB2O5.with a 3. The synthesis, crystal growth and properties of LiK3P2O7 Single crystals of LiK3P2O7 were grown by the spontaneous crystallization with stoichiometric amounts. LiK3P2O7 crystallize in the orthorhombic space group C2221 with a = 6.0373(14) Å, b = 9.339(2) Å, c = 13.292(3) Å, and Z=4. The basic structure units are [P2O7]4- diphosphate groups, consisting of two identical PO4 tetrahedra linked by O(4) atoms. Each [P2O7]4- group is linked to three different LiO4 tetrahedra through its terminal O atoms, while every LiO4 tetrahedron shares its four vertices with three neighboring [P2O7]4- groups to form two-dimensional (2D) infinite ∞[LiP2O7]3- layers extending in the (001) plane. In addition, the ∞[LiP2O7]3- layers are connected together by sharing O atoms with K(1) and K(2) cations located between these layers to generate a three-dimensional network. Thermal analyses, IR spectroscopy, UV-Vis-NIR diffuse reflectance spectra, and band structure calculations are also performed. The calculated band structures and the density of states of the compound suggests that the indirect gap is 4.559 eV.
内容类型	学位论文
源URL	[http://ir.xjipc.cas.cn/handle/365002/4396]
专题	新疆理化技术研究所_材料物理与化学研究室
作者单位	中国科学院新疆理化技术研究所
推荐引用方式 GB/T 7714	曹箭. 新型硼酸盐和磷酸盐化合物的合成、结构和性能研究[D]. 北京. 中国科学院研究生院. 2012.

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