金屬硼酸鹽和碲酸鹽的合成及鑑定;Syntheses and Characterization of Metal Borates and Tellurates

Please use this identifier to cite or link to this item: http://ir.lib.ncu.edu.tw/handle/987654321/80375

Title:	金屬硼酸鹽和碲酸鹽的合成及鑑定;Syntheses and Characterization of Metal Borates and Tellurates
Authors:	張瓈云;Zhang, Li-Yun
Contributors:	化學學系
Keywords:	非線性光學;硼酸鹽;碲酸鹽;水熱合成;封閉系統系下的熔鹽法;共邊八面體之三聚體;Nonlinear optics;Borates;Tellurates;high-temperature, high-pressure hydrothermal method;flux growth method in the closed system;Edge-Sharing Octahedral Trimers
Date:	2019-07-17
Issue Date:	2019-09-03 14:27:33 (UTC+8)
Publisher:	國立中央大學
Abstract:	本論文利用在封閉系統下的熔鹽法及高溫高壓水熱法分別合成出兩個新穎結構的化合物，Ca27[B124O202(OH)22] (1)及 Ca10Na10[Te9O42](H2O) (2)，兩個化合物皆藉由單晶 X光繞射方法鑑定出化合物的晶體結構，再以粉末X光繞射分析比對理論圖，確定樣品純度，並用EDS確定化合物元素組成，而當中只有化合物2獲得純相，並更進一步測量其IR與XPS來分別確定水分子的存在與碲價數。化合物1的空間群為中心對稱的C2/c，結構展現出硼酸基團以共角相連成22員環，並再分別連結兩個無序基團B(OH)2 及B3O2(OH)。經過實驗發現藉由H3BO3分解出微量的水在密閉環境中反應能產生硼酸鹽晶體，並且化合物1的比例與CaO-B2O3-H2O體系組成維度三元圖的趨勢符合。化合物2空間群為中心對稱的 R3 ̅c，結構具有由共邊共享八面體組成的離散線性三聚體[Te3O14]10-，是一種新型只含Te6+-O的有限多聚體(finite oligomer)，其陰離子基團以六方最密堆積成晶胞，而鈣、鈉及水分子位於其中的八面體與四面體的空隙，而位於六方最密堆積層的三聚體，彼此以31螺旋軸旋轉120o，因此具有很長c軸(66.337 Å)。對於合成新穎結構無機材料而言，本研究利用在封閉系統下的熔鹽法及高溫高壓水熱法提供了一個很好的策略，並增加更多新穎結構化合物的發現。;This thesis reports two new structural compounds, Ca27[B124O202(OH)22] (1) and Ca10Na10[Te9O42](H2O) (2), were synthesized by the high-temperature, high-pressure hydrothermal method and the flux growth method in the closed system, respectively. All crystal structures were determined by the single crystal X-ray diffraction. The purity of each compound was confirmed by the good agreement between the calculated and observed powder X-ray diffraction patterns, and verified the element composition by EDS. Only compound 2 product is pure, and further characterized by IR and XPS. The space group of 1 is the centrosymmetric C2/c. The structure consists of the corner-sharing 22 membered rings, which are connected to two disordered groups, B(OH)2 and B3O2(OH), respectively. It has been found through experiments that a small amount of water is decomposed by H3BO3, which can produce borate crystals in a closed environment. The elemental ratio of 1 goes with the tendency of the composition–dimensionality ternary diagram for the CaO-B2O3-H2O systems. The space group of 2 is the centrosymmetric R3 ̅c. The structure consists of discrete linear edge-sharing octahedral trimers with the composition [Te3O14]10-, which is a new type of finite Te-O oligomer with Te6+ only. The anions groups form a hexagonal close-packed lattice with the octahedral and tetrahedral interstices being filled with Ca2+ and Na+ cations and water molecules. The octahedral trimers in every other h.c.p. layers rotate around the 31 screw axis for 120°, therefore the unit cell has a very long c axis (66.337 Å). For the syntheses of novel structural inorganic materials, this study provides good strategys, and adds more novel structural compounds to the discovery.
Appears in Collections:	[Graduate Institute of Chemistry] Electronic Thesis & Dissertation

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