Synthesis and Crystal Structure of aCopper
InSeI单晶的制备及其结构与性能研究
第49卷第12期人工晶体学报Vol.49No.12 2020年12月JOURNAL OF SYNTHETIC CRYSTALS December,2020 InSei单晶的制备及其结构与性能研究周玄1,2,程国峰2,何代华1(1.上海理工大学材料科学与工程学院，上海200093；2.中国科学院上海硅酸盐研究所，上海200050)摘要:利用化学气相传输法(CVT)制备了InSeI单晶。
该晶体为黄色的针状物，晶体较脆。
在室温下进行X射线衍射分析发现，其属于四方晶系，晶胞参数为a=b=1.8643(5)nm,c=1.0120(3)nm,V=3.5172nm3,空间群为他/a。
紫外可见光吸收光谱、光致发光光谱等结果显示该晶体的禁带宽度是2.48eV,在一定波段光的激发下,InSeI单晶在600nm左右有较宽的发射峰，表明该晶体的发光方式为缺陷态发光。
介电温谱表明InSeI单晶在440K时其四方相的结构发生了相变。
关键词:InSeI;金属基硫卤化合物;化学气相传输法;光致发光;禁带宽度;介电性能中图分类号：O78文献标识码:A文章编号：1000-985X(2020)12-225244 Synthesis,Structure and Properties of InSei Single CrystalsZHOU Xuan1,2,CHENG Guofeng2,HE Daihua1(1.School of Materials Science and Engineering,Lniversity of Shanghai for Science and Technology,Shanghai200093,China；2.Shanghai Institute of Ceramics,Chinese Academy of Sciences,Shanghai200050,China)Abstract:InSeI single crystals were synthesized by the chemical vapor transport(CVT)method.The crystal is yellow needleshaped and brittle.X-ray diffraction results at room temperature show the tetragonal system of InSeI，with lattice parameters of a=b=1.8643(5)nm,c=1.0120(3)nm,V=3.5172nm3,and space group is/a.The ultraviolet-visible absorption spectrum，photoluminescence spectrum results show that InSeI has a2.48eV band gap，under the excitation of a certain band of light，InSeI single crystal has a wide emission peak at about600nm，which indicates that the luminescence mode of the crystal is defect state luminescence.The dielectric temperature spectrum indicates that a phase transition happened in the tetragonal structure of InSeI crystals at440K.Key words:InSeI;metal based thiohalide;chemical vapor transport method;photoluminescence;band gap;dielectric property0引言近年来，金属基硫卤化合物MQX［1］(M=Ga,In,Sb,Bi；Q=S,Se,Te；X=Cl,Br,I)由于其独特的光电性质如铁电性［2-3］、热电性［4］、光电导性［5］和非线性光学性能［6］等引起了科学界的浓厚兴趣。
Isolation and Crystal Structure of 2—Bromoaldisin
Isolation and Crystal Structure of 2—Bromoaldisin 徐效华; 陈晓; 等【期刊名称】《《结构化学》》【年(卷),期】2001(020)003【摘要】The crystal structure of the title compound (C8H7BrN2O2,Mr=243.07) was isolated from the marine sponge Phacellia fusca Schmidt collected from the South China Sea. Its crystal structure was determined by single-crystal X-ray diffraction. The crystal is orthorhombic with space group Pbca, a=12.9952(8), b=7.4479(5), c=18.598(1) ?, V=1800.1(2) ?3, Z=8, Dc=1.794g/cm3, (=0.71073 ?, ( (MoK()=4.533mm-1, F(000)=960. The structrue was refined to R=0.0349, wR(F2)=0.0925 for 1589 reflections with I > 2((I). X-ray diffraction analysis reveals that the title compound has one five-membered pyrrole ring and one seven-membered azepin ring. There are two intermolecular hydrogen bonds between two molecules.【总页数】3页(P173-175)【作者】徐效华; 陈晓; 等【作者单位】InstituteandStateKeyLaboratoryofElemento－OrganicChemistry NankaiUniversity Tianjin300071 China【正文语种】中文【中图分类】O626【相关文献】1.Isolation, Crystal Structure and Antitussive Activity of 9S,9aS-neotuberostemonine [J], WU Yi;YE Qing-Mei;LIU Jing;XU Wei;ZHU Zi-Rong;JIANG Ren-Wang2.Isolation, Crystal Structure and Na+/K+-ATPase Inhibitory Activity of 1β-Hydroxydigitoxigenin [J], XU Yun-Hui;XU Jian;JIANG Xue-Yang;CHEN Zhi-Hua;XIE Zi-Jian;JIANG Ren-Wang;FENG Feng3.Isolation and Crystal Structure of Ent-kaurane Diterpenes from Rubus corchorifolius L.f. [J], CHEN Xue-Xiang;HUANG Jian-Xi;OU Yang-Wen;LIU Xiao-Juan;ZHOU Li-Ping;CAO Yong4.Isolation, Crystal Structure,and Anti-inflammatory Activity of Sakuranetin from Populus tomentosa [J], LIU Hai-Ping;CHAO Zhi-Mao;TAN Zhi-Gao;WU Xiao-Yi;WANG Chun;SUN Wen5.Isolation and Crystal Structure of 2-Bromoaldisin [J], 徐效化; 陈晓; 廖仁安; 谢庆兰因版权原因，仅展示原文概要，查看原文内容请购买。
（物理化学专业论文）系列Co配位聚合物的合成、结构及自旋转换和光—电性能的研究
系列Ｃｏ配位聚合物的合成，结构及自旋转换和光一电性能的研究系列Ｃｏ配位聚合物的合成、结构及自旋转换和光一电性能的研究博士生：金晶指导教师：牛淑云教授专业：物理化学方向：功能分子设计与研制摘要配位聚合物是金属离子和有机配体通过自组装而形成的无限结构的配位化合物。
由于它在光、电、磁、催化等领域具有诱人的应用前景，被认为是当前最有潜在能力的功能材料，已成为无机化学和材料化学领域的研究热点之一。
它的目标是通过金属离子和有机配体间的相互作用，设计合成具有理想结构和特定功能的稳定分子体系和特殊功能的材料。
本文围绕当前关于配位聚合物研究的若干热点，采用溶剂热合成、水热合成和微波合成等方法，以Ｃｏ（ＩＩ）或Ｃｏ（ＩＩＩ）为中心原子，通过与有机配体的自组装，共合成了ｌＯ种Ｃｏ（ＩＩ）或Ｃｏ（ＩＩＩ）及Ｆｅ（ＩＩＩ）的配位聚合物和３种Ｃｏ（ＩＩ）的二聚物，它们的分子式如下：（１）｛［ｃｏ（ｐ·４，４’ｂｉｐｙ）（４，４’·ｂｉｐｙ）２（Ｈ２０）２］，（ＯＨ）３－（Ｍｅ４Ｎ）‘４，４’－ｂｉｐｙ。
４Ｈ２０｝ｎ（２）｛［Ｃｏ（ｐ－４，４’一ｂｉｐｙ）（Ｈ２０）４］－ＳＵＣ－４Ｈ２０｝。
（３）［Ｃ０２（Ｉａ２一ｂｔｅｃ）（ｐｈｅｎ）２（Ｈ２０）４］（４）【Ｃ０２（９２一ｂｔｅｃ）（ｂｉｐｙｈ（Ｈ２０）４‘Ｈ２０（５）［Ｃ０２（１ａ２－ｂｔｅｃ）（ｐｈｅｎ）２（Ｈ２０）ｄ·２Ｈ２０（６）ｆＣ０４（出一ｂｔｅｃ）（ｂｉｐｙ）４（ＨｚＯ）４］ｎ（７）［Ｆｅ２（№一ｂｔｅｃ）（Ｉ＿ｔ２－Ｈ２ｂｔｅｃ）（ｂｉｐｙ）｝２（Ｈ２０）２１ｎ（８）［Ｆｅ２（ｋｔ２－ｂｔｅｃ）（ｐａ—Ｈ２ｂｔｅｃ）（ｐｈｅｎｈ（Ｈ２０）２１ｎ（９）［Ｃｏ（ｐｈｅｎ）（Ｈ２０）（№一ｂｔｅｃ）ｏ５】ｎ（１０）｛［Ｃｏ（ｐ＿４－ｂｔｅｃ）ｏ５（Ｈ２０）２】－５Ｈ２０｝ｎｌ—————————！！堕堡！燮鱼竺竺竺皇：苎苎垦！垦竺垫竺垄二皇兰堂竺竺窒（１１）【ｃｏ（№一ＣＨ２（ＣＯＯ）２）（４，∥－ｂｉｐｙ）０５（Ｈ２０）］Ⅱ（１２）【ｃｏ（№一ＨｃＯＯ）ｄｃｏ（Ｈ２０）４】。
拉曼光谱测量钙钛矿电声耦合强度
拉曼光谱测量钙钛矿电声耦合强度1.拉曼光谱是一种用于分析晶体材料结构和性质的强大技术。
Raman spectroscopy is a powerful technique for analyzing the structure and properties of crystalline materials.2.钙钛矿是一类具有重要电声耦合特性的材料。
Perovskite is a type of material with important electroacoustic coupling properties.3.通过拉曼光谱，可以了解钙钛矿中电声耦合的强度和机制。
Raman spectroscopy can be used to understand the strength and mechanism of electroacoustic coupling in perovskite.4.钙钛矿的电声耦合特性对于光伏和光电器件的性能至关重要。
The electroacoustic coupling properties of perovskite are crucial for the performance of photovoltaic and optoelectronic devices.5.拉曼光谱可以提供关于晶体结构、相变和电子结构的丰富信息。
Raman spectroscopy can provide rich information about crystal structure, phase transitions, and electronic structure.6.钙钛矿材料的电声耦合性质直接影响着其光电器件的效率和稳定性。
The electroacoustic coupling properties of perovskite materials directly affect the efficiency and stability oftheir optoelectronic devices.7.拉曼光谱测量可以帮助科学家们深入了解钙钛矿材料的微观特性。
药物共晶的合成和结构分析
2017年2月 CIESC Journal ·509·February 2017第68卷 第2期 化 工 学 报 V ol.68 No.2DOI ：10.11949/j.issn.0438-1157.20160928药物共晶的合成和结构分析黄耀辉1，尹秋响1,2，张霞1，郭明霞1，王昌1（1化学工程联合国家重点实验室，天津大学化工学院，天津 300072；2化学化工协同创新中心，天津 300072） 摘要：药物的理化性质与其结晶形式相关，药物共晶作为一种新型的固态形式能够在不影响药物内部结构的同时改善药物的多方面性质，提高药效。
通过药物共晶的定义、应用、制备方法和结构研究等方面对目前药物共晶的研究现状进行总结，为后续共晶方向的研究提供理论指导。
关键词：药物共晶；合成；结晶；结构研究；化学过程中图分类号：TQ 460.1 文献标志码：A 文章编号：0438—1157（2017）02—0509—10Synthesis and structural analysis of pharmaceutical co-crystalsHUANG Yaohui 1, YIN Qiuxiang 1,2, ZHANG Xia 1, GUO Mingxia 1,WANG Chang 1(1State Key Laboratory of Chemical Engineering , School of Chemical Engineering and Technology , Tianjin University , Tianjin 300072, China ; 2Collaborative Innovation Center of Chemical Science and Chemical Engineering , Tianjin 300072, China )Abstract : Co-crystals have advantages in physiochemical properties over their constituent components and are expected to use in product formulation such as enhanced active pharmaceutical ingredients, food components withimproved absorbability, and specialty chemicals with better performance. The development of pharmaceuticalco-crystals might offer advantages over the active pharmaceutical ingredients and overcome some of the limitations encountered with classical strategy (polymorph, solvate and salt formation). In recent years, co-crystals have recently gained much attention for pharmaceutical development especially because it has great advantages in improving the solubility, dissolution, melt point and oral bioavailability. Since the co-crystals lattice comprises two or more kinds of molecules, compared with the conventional structure of the drug crystal, intermolecular force comprising more types such as hydrogen, halogen bond, van der Waals forces, π-π interaction, so the structure is more complex. The research on the co-crystals structure can be helpful to understand the formation mechanism. The definition, application, preparation and structure of co-crystals were reviewed, it will provide theoretical guidance for the studies of the following research.Key words : pharmaceutical co-crystals; synthesis; crystallization; structural study; chemical processes引 言药物能够以多种不同的固态形式存在，如多晶型、溶剂化合物、盐、共晶和无定形等，每种固态形式都具有自身独特的理化性质，进而影响药物的溶解度、稳定性、生物利用度等性能[1]，而药物的疗效很大程度上取决于活性药物成分自身的理化性质及其固体形态。
应用Caco-2细胞模型进行毒性中药研究的思路
等。研究表明 I相代谢酶如细胞色素 P450( CYP450)、 II相代谢酶如 UDP - 葡萄糖醛酸转移酶、磺基转移酶 和谷胱甘肽硫基转移酶在 Caco- 2细胞中也存在, 并
国外广泛使用 [ 1 ~ 3] 。本世纪初, 国内有学者经研究预 保持了 P - 糖蛋白高表达的 特征。以 上特点决 定了
四、利用 C aco- 2细胞模型研究毒性中药的思路
1 确定毒性中药的肠道吸收成分 Caco- 2细胞经毒性中药染毒后, 收集被细胞吸 收或穿透 C aco - 2细胞单细胞层的成分, 采用高效液 相法将收集到的物质与实验药物的固有成分 进行比
内两侧药物的含量变化或细胞中的药物含量变化。计 算 Papp (表观穿透系数 ) 及 Papp1 /Papp2 ( Papp1为基底面至 绒毛面方向测得的表观穿透系数; Papp2为绒毛面至基 底面方向测得的表观穿透系数 ) 的数值, 以确定吸收 成分的吸收机制。 P - 蛋白 ( P - ly - oprote in, P - gp) 和多药耐药蛋白 ( m ulti- rug resistance protein, MRP ) 是 Caco- 2细胞中两种主要转运蛋白。两者均为能量 ( ATP) 依赖性膜蛋白。我们可通过细 胞基底面及绒 毛面两侧不同方向转运速率的比较及检测加入转运蛋 白抑制剂后 Papp值的变化确定吸收成分的转运机制。
世界科学技术 中医药现代化 思路与方法
应用 Caco- 2细胞模型进行 毒性中药研究的思路
# 罗明媚 刘树民
索 晴 ( 黑龙江中医药大学 哈尔滨 150040)
摘 要: 本文概述了 C aco- 2细胞模型的基本特点、培养方法及其在中药研究方面的应用, 提出了 应用 C aco- 2细胞模型对毒性中药进行研究的新思路。
邻苯二甲酸根桥联多核铜配位聚合物的合成与晶体结构_英文_
Synthesis and Crystal Structure ofPhthalate Copper (Ⅱ)polymeric TIAN Li 1, CHEN Lin 1, YI Lanhua2(1.Department of Chemistry ,X iangtan N ormal University ,Hunan X iangtan 411201China ;2.Chemistry Institute of X iangtan University ,X iangtan 411105China )【Abstract 】 A phthalate copper (Ⅱ)polymeric has been synthesized ,namely {[Cu (Phth )(Phen )(H 2O )]・(H 2O )}n ,where Phth denotes phthalate and Phen denotes 1,10-phenanthroline.The crystal structure of the complex was deter 2mined by single crystal X -ray diffraction ,the result of which shows that the complex crystallizes in orthorhombic with space group Pca21,a =1.1159(3)nm ,b =1.1640(2)nm ,c =1.4066(5)nm ,Z =4,V =1.8270(9)nm 3,F (000)=908,D c =1.614mg.m-3,μ(M O K a )=1.238mm -1.The final R =0.0351,wR (F 2)=0.0891were based on1455observed independent reflections with F 0>4σ(F 0).X -ray analysis revealed that the m olecular is polymeric with extended phthalate bridges to form one -dimensional chain structure and that the copper (Ⅱ)ion is five -coordinated in a distorted square pyramid.K ey w ords : synthesis ;polymeric ;crystal structure邻苯二甲酸根桥联多核铜配位聚合物的合成与晶体结构Ξ田 俐1, 陈 琳1, 易兰花2(1.湘潭师范学院化学化工系,湖南湘潭411201;2.湘潭大学化学学院,湖南湘潭411105)[摘要] 合成了邻苯二甲酸根桥联多核铜的配位聚合物{[Cu (Phth )(Phen )(H 2O )]・(H 2O )}n ,(Phth :邻苯二甲酸根二阶阴离子;Phen :1,10邻菲咯啉),并得到了它的单晶.用X -射线单晶衍射法测定了配合物的晶体结构.晶体学数据如下:经验式为C 20H 16CuN 2O 6,Mr =443.89,晶体属正交晶系,Pca21,a =1.1159(3)nm ,b =1.1640(2)nm ,c =1.4066(5)nm ;Z =4,V =1.8270(9)nm 3,F (000)=908,Dc =1.614mg.m -3,μ=1.238mm -1.晶体结构由直接法解出,数据用全矩阵最小二乘法进行修正,最终结构偏差因子R =0.0351,wR =0.0891,吻合因子S =0.991,晶体中每个Cu (Ⅱ)离子配位数为5,这5个配位原子形成一个畸变的四方锥结构,配合物分子通过邻苯二甲酸根桥联呈无限延伸的一维链状结构,配合物通过分子间氢键作用形成三维网状结构.关 键 词:桥联金属多核铜配位聚合物;合成;晶体结构中图分类号:O631.1 文献标识码:A 文章编号:10005900(2003)010113041 I ntroductionP olymeric with extended ligand bridges have been widely inverstigated in the past decades [1,2].Interest in thisarea stems from attem pts to mimic the structural and functional properties of biological systems and to design andsynthesize m olecular magnets[3,4].As it has been known that phthalic is a g ood extended ligand bridge [5].Many phthalate metal com plexes have been prepared and their structures ,magnetic and spectroscopic properties have been studied recently [6].H owever ,to our knowledge ,A little single crystal structure of this kind has been reported.In this paper ,we have synthesized the phthalate copper polymeric ,the single crystal structure of which was determined by X -ray crystallography diffraction method for the first time.第25卷第1期2003年3月 湘 潭 大 学 自 然 科 学 学 报Natural Science Journal of X iangtan University V ol.25N o.1Mar.2003Ξ收稿日期:20020919 基金项目:湖南省教育厅资助项目(02C464) 作者简介:田 俐(1973),男,湖南攸县人,讲师.2 Experimental2.1 R eagentCu(NO3)・3H2O,phthalic acid,1,10-phenanthroline,K OH were of analytical grade.2.2 Synthesis of single crystalPhthalic acid(0.166g,1mm ol),Phen(0.198g,1mm ol)were diss olved in30m L of EtOHΠH2O(VΠV 1∶1)s olution adjusted to pH=7～8by addition of40%K OH s olution,and then the s olution was added dropwise with Cu(NO3).3H2O(0.246g,1mm ol)in10m L of H2O.The resulting s olution was stirred at50～60℃for6h and filtered.The blue precipitate was filtered off.The filtrate yielded blue hexag on crystals after standing in air at room tem perature for six m onths.Elemental analysis(%):Calad.F or C20H16CuN2O6:C,54.11;H,3.63;N,6.31;F ound:C,54.03;H,3.62;N,6.29.2.3 Structure DeterminationA blue hexag on single crystal(0.50mm×0.36mm×0.20mm)was m ounted on a glass fiber.Data C ollec2 tions were performed on a Siemens P4diffractometer with graphite m onochromated M O K a radiation(λ=0.071073 nm).Unit cell dimensions were obtained from a least-squares refinement using27carefully centered reflections in 2.90°<θ<15.95°range.A total of2102reflections were collected at292(2)K withω-2θscan m ode in the rang of3.5°<2θ<50.0°of which1821independent reflections were obtained.Am ong them1455observed were used for refinement with275variable parameters.The structure was s olved by direct methods and succeeding differ2 ence F ourier syntheses.A full-matrix least-squares refinement gave final R=0.0351,w R(F2)=0.0891 and S=0.991withω=1Π[σ2(F20)+(0.0652p)2]while P=(F20+2F20)Π3.The maximum and minimum re2 sidual peaks on the final difference F ourier map were514e(nm)-3and-605e(nm)-3,respectively.T ab.1 N on-hydrogen atomic coordinates[×104]and equivalentisotropic displacement p arameters[(nm2×10)(U eq)]表1 配合物非氢原子坐标(×104)和等效各向同性温度因子[(nm2×10)(U eq)]X Y Z U eqΠnm2×10 Cu1135(1)5233(1)5973(3)26(1)N(1)995(9)3925(9)5042(7)21(2)N(2)942(10)3963(10)6923(9)35(3)O(1)1397(8)6111(8)6910(7)39(2)O(2)3138(8)5847(7)7462(7)36(2)O(3)3697(7)6434(8)10032(6)28(2)O(4)1863(7)5807(7)9489(8)35(2)O(5)-999(3)5516(3)5988(9)36(1)C(1)2642(9)6508(10)9540(8)27(3)C(2)2630(10)7575(10)9005(8)25(3)C(3)2746(9)8701(10)9427(9)32(3)C(4)2611(10)9674(8)8960(11)34(3)C(5)2389(11)9701(11)7991(11)45(4)C(6)2271(11)8606(10)7508(10)35(3)C(7)2386(10)7649(9)8027(9)24(3)C(8)2228(10)6516(8)7421(8)28(3)C(9)979(11)3972(11)4117(10)36(3)C(10)748(14)2996(13)3568(11)42(4)C(11)409(11)1984(9)3997(11)41(4)C(12)406(12)1914(12)4970(11)38(3)C(13)96(11)942(11)5498(12)37(4)C(14)88(13)907(12)6451(15)53(5)C(15)381(10)1958(12)6995(10)34(3)C(16)429(12)2030(12)8007(9)45(4)C(17)705(13)3030(12)8446(10)40(4)C(18)991(11)3963(13)7882(9)35(3)C(19)667(10)2897(9)6484(8)27(3)C(20)689(10)2982(10)5450(8)35(3)O(6W)-649(7)8056(5)6021(18)135(3) 1) U(eq)is defined as one third of trace of the orthog onalie Uij tens or.411 Natural Science Journal of X iangtan University 20033 R esults and discussionNon -hydrogen atomic coordinates and equivalent thermal parameters are listed in T able 1.The selected bond lengths and bond angles are given in T able 2and T able 3,respectively .The packing diagram of the title m olecules in a unit cell is illustrated in Fig.1.and the m olecular structure of the com plex is shown in Fig.2.T ab.2 Selected bond lengths [L b ]表2 配合物主要键长(L b )L b ΠnmL b ΠnmL b ΠnmCu -O (1)0.1923(10)Cu -O (3)310.1934(8)Cu -N (2)0.2004(12)Cu -N (1)0.2014(10)Cu -O (5)0.2404(3)N (1)-C (20)0.1285(16)N (1)-C (9)0.1302(18)N (2)-C (18)0.1349(18)N (2)-C (19)0.1420(15)O (1)-C (8)0.1181(14)O (2)-C (8)0.1281(12)O (3)-C (1)0.1369(12)O (3)-Cu 330.1934(8)O (4)-C (1)0.1195(13)C (1)-C (2)0.1451(15)C (2)-C (7)0.1406(7)C (2)-C (3)0.1444(15)C (3)-C (4)0.1317(17)C (4)-C (5)0.1386(8)C (5)-C (6)0.1450(18)C (6)-C (7)0.1338(16)C (7)-C (8)0.1579(14)C (9)-C (10)0.1398(18)C (10)-C (11)0.1377(19)C (11)-C (12)0.1371(19)C (12)-C (13)0.1400(2)C (12)-C (20)0.1449(16)C (13)-C (14)0.1341(8)C (14)-C (15)0.1480(2)C (15)-C (19)0.1347(18)C (15)-C (16)0.1426(18)C (16)-C (17)0.1353(19)C (17)-C (18)0.1383(18)C (19)-C (20)0.1459(8)T ab.3 Selected bond angles[θb ]表3 配合物主要键角(θb )θb Π(°)θb Π(°)θb Π(°)O (1)-Cu -O (3)386.49(14)O (1)-Cu -N (2)94.5(5)O (3)3-Cu -N (2)178.6(5)O (1)-Cu -N (1)174.7(4)O (3)3-Cu -N (1)96.2(5)N (2)-Cu -N (1)82.41(16)O (1)-Cu -O (5)92.7(3)O (3)3-Cu -O (5)90.2(3)N (2)-Cu -O (5)89.3(4)N (1)-Cu -O (5)91.8(3)C (20)-N (1)-C (9)118.5(11)C (20)-N (1)-Cu 112.1(8)C (9)-N (1)-Cu 128.3(9)C (18)-N (2)-C (19)116.3(11)C (18)-N (2)-Cu 128.3(9)C (19)-N (2)-Cu 112.2(9)C (8)-O (1)-Cu 127.6(8)C (1)-O (3)-Cu 33118.4(7)O (4)-C (1)-O (3)127.8(10)O (4)-C (1)-C (2)123.2(10)O (3)-C (1)-C (2)108.9(9)C (7)-C (2)-C (3)111.3(12)C (7)-C (2)-C (1)124.1(12)C (3)-C (2)-C (1)124.3(10)C (4)-C (3)-C (2)124.4(12)C (3)-C (4)-C (5)122.0(13)C (4)-C (5)-C (6)124.4(12)C (7)-C (6)-C (5)117.9(13)C (6)-C (7)-C (2)127.1(12)C (6)-C (7)-C (8)113.0(10)C (2)-C (7)-C (8)119.9(12)O (1)-C (8)-O (2)125.9(11)O (1)-C (8)-C (7)120.2(9)O (2)-C (8)-C (7)113.3(10)N (1)-C (9)-C (10)121.4(13)C (11)-C (10)-C (9)120.3(14)C (12)-C (11)-C (10)119.3(13)C (11)-C (12)-C (13)125.4(13)C (11)-C (12)-C (20)114.5(13)C (13)-C (12)-C (20)120.1(14)C (14)-C (13)-C (12)123.9(16)C (13)-C (14)-C (15)119.4(17)C (19)-C (15)-C (16)118.4(13)C (19)-C (15)-C (14)116.5(13)C (16)-C (15)-C (14)125.0(14)C (17)-C (16)-C (15)121.0(13)C (16)-C (17)-C (18)117.7(13)N (2)-C (18)-(17)124.4(12)C (15)-C (19)-N (2)121.9(11)C (15)-C (19)-C (20)126.3(13)N (2)-C (19)-C (20)111.8(13)N (1)-C (20)-C (12)125.7(11)N (1)-C (20)-C (19)120.5(12)C (12)-C (20)-C (19)113.8(13) Symmetry trans formations used to generate equivalent atoms :3:-X +1Π2,Y,Z -1Π2; 33:-X +1Π2,Y,Z +1Π2As shown in the figures ,the m olecule is polymeric with extended phthalate bridges to form one -dimensional chain structure.The copper (Ⅱ)ion is five -coordinated with tw o N atoms of the ligand Phen and three O atoms from tw o phthalates and H 2O respectively ,occupying site at the base of a distorted square pyramid capped by the O atom from H 2O.The interm olecular hydrogen bonding interactions join the m olecules to form three -dimensional web structure which is shown in Fig.3.The uncoordinated water m olecule connects with the coordinated water m olecule (O (6W )…O (5)=0.2983(3)nm ,H (6A )…O (5)=0.257(9)nm ,O (6w )-H (6A )…O (5)=113(7)°)inv olving H (5A )atom (O (2)…O (5)=0.2782(14)nm ,H (5A )…O (2)=0.207(3)nm ,O (5)-H (5A )…O (2)=143(5)°)and H (5B )atom bonded with O (4)(O (4)…O (5)=0.2784(13)nm ,H (5B )…O (4)=0.1960(19)nm ,O (5)-H (5B )…O (4)=170(7)°).511N o.1 TI AN Li et al Synthesis and Crystal S tructure of Phthalate C opper (Ⅱ)polymeric Fig.1 Arrangement of the com plex in unit cell图1 配合物分子在晶胞中的排列Fig.2 M olecular structure of the com plex图2 配合物的分子结构R eferences[1] W illett R D ,G attesschi D ,K ahn O (Eds ).M agmeto -S tructure C orrelations in Exchange C oupled Systems[M].NAT O ASI Series C 140,ReidelPress ,1985.[2] M iller J S (Eds ).Extended Linear Chain C om pound[M].Plenum Press ,1983.[3] Xue F C ,Jiang Z Y,Liao D Z ,et al.Synthesis and Characterization of new μ-phthalate trinuclear C opper (Ⅱ)and Nickle (Ⅱ)com plexes[J ].Acta Sci Nat Univ N orm HuNan ,1993,16(3):241-245.[4] Shi J M ,Liao D Z ,Jiang Z H ,et al.Synthesis ,M agnetism and Cancer -Inhibiting Activity of μ-4-Nitrophthalato Binuclear C obalt (Ⅱ)C om 2plexes[J ].Chin J Appl Chem ,1996,13(4):86-88.[5] Li X Y,Jiang Z H ,Liao D Z ,et al.Synthesis ,S pectrum and M agnetism of μ-phthalate Binuclear real earths C om plexes with 5-Nitro -1,10-phenanthroline[J ].J Inorg Chem ,1994,10(2):184-187.[6] M iao M M ,Sun X R ,Shi J M ,et al.Synthesis and M agnetism of T etrabrom ophthalate -Bridged C obalt (Ⅱ)Binuclear C om plexes[J ].Chin J Appl Chem ,1996,13(1):42-45.611 Natural Science Journal of X iangtan University 2003。
a new supermolecular compound18冠
Synthesis and crystal structure of a new supermolecular compound: [C12H24O6][H3PMo12O40]·22H2O(C12H24O6 18-crown-6) Wansheng You a,Enbo Wang a,*,Qinglin He a,Lin Xu a,Yan Xing b,Hengqing Jia ba Northeast Normal University,Department of Chemistry,Changchun Jilin130024,People’s Republic of Chinab Changchun Institute of Applied Chemistry,Academic Sinica,Changchun Jilin130022,People’s Republic of ChinaReceived8October1999;received in revised form9November1999;accepted9November1999AbstractThe title compound,[C12H24O6][H3PMo12O40]·22H2O,was synthesized by the self-assembly of18-crown-6(abbreviated as C12H24O6or18C6)and H3PMo12O40in the mixed solvent of CH3OH and CH3CN,and was characterized by IR,1H NMR and X-ray diffraction for thefirst time.Crystal data:Triclinic,P 1;a 13:428 3 A;b 13:557 3 A;c 14:642 3 A;a 105:39 3 Њ;b 90:06 3 Њ;g 119:56 5 Њ;V 2207:5 8 A3;Z 1;R1 0:0719;wR2 0:1990:It has a disordered a-Keggin PMo12O3Ϫ40anion,which contains the strong alternating short(mean1.844A˚)and long(mean1.958A˚)Mo–O–Mo bonds.In the unit cell,crown ethers and molybdophosphates are alternatively arranged in good order along c-axis.An oxonium ion is located at the center of a crown ether molecule.,Oxonium ion interacts with18C6by the means of hydrogen bonds(mean 2.7771A˚),which are electrostatic or resonant.The observations show the existence of[H3O(C12H24O6)]ϩ.᭧2000Elsevier Science B.V.All rights reserved.Keywords:Molybdophosphate;Crown ethers;Oxonium ion;Hydrogen bonds;X-ray crystallography1.IntroductionSupermolecular compounds of polyoxometalates, or hybrid materials,produced by combining different inorganic and organic moieties by means of molecular assemblies,are of current interest in some important areas of chemistry such as catalysis,non-linear optical materials,liquid crystals and charge-transfer salts[1–3].Crown ethers have excellent ability of molecular recognition.Furthermore,combining crown ether molecules with polyoxometalates would open up broadfields for studies on supermolecular compounds and hybrid materials[4,5].Thefirst oxonium–crown ether complexes wereobtained by Izatt et al.[6];they consisted ofH3Oϩand dicyclohexano-18-crown-6adductsassociated with ClOϪ4and PFϪ6counterions.There-after,some adducts of oxonium ion and crownether were obtained,associated with BFϪ4;CIOϪ4; PFϪ6;IϪ,BrϪ,PtCl2Ϫ6;SbFϪ6and CF3SOϪ3ions[7–9].In these studies,it was generally assumed thatH3Oϩion in the adducts is located at or near thecenter of the macrocyclic ether cavity and thiswould maximize the electrostatic interactionbetween the two units.This was also expectedon the basis of the strong hydrogen bonds asrevealed by IR spectra.To our acknowledge,thishypothesis had been confirmed by only one X-raydiffraction study on[18C6][H3OϩBF4][10].Thelimited number of the crystal structure data hasJournal of Molecular Structure524(2000)133–1390022-2860/00/$-see front matter᭧2000Elsevier Science B.V.All rights reserved.PII:S0022-2860(99)00447-0www.elsevier.nl/locate/molstruc*Corresponding author.Tel.:ϩ86-43-1562-3492;fax:ϩ86-43-1568-4009.E-mail address:huchw@(E.Wang).hampered the structural study on the interaction between the oxonium ion and crown ether.To the best of our knowledge,the adducts of oxonium ion and crown ether associated with polyox-ometalates have not been reported so far.We describe herein the synthesis and crystal structure of a new supermolecular compound of crown ether and poly-oxometalate acid:[C12H24O6][H3PMo12O40]·22H2O.It is a good example of an interaction between crown ether and the oxonium ion.2.Experimental2.1.Materials and methodsAll chemicals purchased were of reagent grade and used without further purification.Infrared spectrum was recorded as KBr pellets on a Nicolet170SX FT-IR spectrometer;1H NMR spectrum was obtained with a Bruker Am-500spectrometer operating at 500MHz using CD3OD-d4as solvent.C,H elemental analysis were performed on Perkin–Elmer240c Elemental analyzer.P and Mo elemental analysis were performed on a PLASMA SPECI(I)quant-ometer.TG analysis was performed on a Q-Derivato-graph thermal analyzer.2.2.Preparation of[C12H24O6]·[H3PMo12O40]·22H2O H3PMo12O40was prepared according to the litera-ture[11].18C6(0.1g)in20ml acetonitrile was added drop-wise to a20ml methyl alcohol solution of0.8g H3PMo12O40with stirring for1h.The yellow solution was allowed to stand for3–5days and the product, [C12H24O6][H3PMo12O40]·22H2O,was collected. Yield:25%.Anal.calc.:C,5.8;H,2.8;P,1.2;Mo, 46.3%;found:C,6.0;H,2.9;P,1.1;Mo,45.7%.Calc. total loss was28.8%;found30.1%.2.3.X-ray crystallographyThe data were collected on Siemens P4four-circle diffractometer(Mo-Ka radiation l 0:71073 A;v–2u scan mode).A yellowish-green single crystal wasW.You et al./Journal of Molecular Structure524(2000)133–139134Table1Crystal data and structure refinementEmpirical formula C12H71Mo120O68PFormula weight2485.97Temperature293(2)KWavelength0.71073A˚Crystal system TriclinicSpace group P 1Unit cell dimensions a 13:428 3 A a 105:39 3 Њb 13:557 3 A b 90:06 3 Њc 14:642 3 A g 119:56 5 ЊVolume,z2207.5(8)A˚3,1Density(calc.) 1.870Mg/m3Absorption coefficient 1.758mmϪ1F(000)1206Crystal size0:46×0:38×0:16mm3u Range for data collection 1.95–23.01Limiting indicesϪ1ՅhՅ13;Ϫ13ՅkՅ12;Ϫ16ՅlՅ16Reflections collected7071Independent reflections5937 R int 0:0184Max.and min transmission0.62097and0.51046Data/restraints/parameters5927/152/433Goodness-of-fit on F2 1.004Final R indices IϾ2s I R1 0:0719;wR2 0:1990R indices(all data)R1 0:1057;wR2 0:2271Extinction coefficient0.0008(2)Largest diff.peak and hole 1.291andϪ0.816e A˚Ϫ3mounted inside a glass capillary.A semiempirical absorption correction (PSISCAN)was applied.The hydrogen atoms of crown ether were introduced in calculated positions with fixed C–H distance andisotropic displacement parameters C–H 0:97 Afor ϾCH 2and U iso 0:08 A2 :A summary of the crystallographic data and structure parameters for [C 12H 24O 6][H 3PMo 12O 40]·22H 2O is provided in TableW.You et al./Journal of Molecular Structure 524(2000)133–139135Table 2Atomic coordinates ×104 and equivalent isotropic displacementparameters A×103 for [C 12H 24O 6][H 3PMo 12O 40]·22H 2O.U (eq)is defined as one-third of the trace of the orthogonalized U ij tensorxy z U (eq)Mo(1)2433(1)6262(1)6801(1)63(1)Mo(2)Ϫ1565(1)1869(1)3801(1)64(1)Mo(3)Ϫ2842(1)3185(1)5448(1)66(1)Mo(4)1027(1)3185(1)5447(1)67(1)Mo(5)Ϫ392(1)4215(1)7159(1)65(1)Mo(6)Ϫ1172(1)6262(1)6806(1)64(1)P 05000500046(1)O(1)Ϫ2264(4)443(4)3230(3)84(2)O(2)Ϫ4136(4)2308(5)5657(4)85(2)O(3)Ϫ559(5)3893(5)8196(3)101(2)O(4)3552(4)6808(4)7621(4)81(1)O(5)Ϫ1747(4)6818(4)7623(4)81(1)O(6)1445(4)2298(4)5665(4)86(2)O(7)2200(4)4677(4)6177(4)86(2)O(8)305(4)7519(4)6951(3)82(2)O(9)2230(4)7520(4)6971(4)84(2)O(10)1220(4)5520(4)7428(4)84(2)O(11)93(4)3237(4)6463(4)90(2)O(12)Ϫ2516(4)1981(4)4705(4)90(2)O(13)Ϫ1866(4)3235(4)6470(4)85(2)O(14)Ϫ3161(4)3394(4)4309(4)87(2)O(15)Ϫ1560(5)6629(5)5714(4)92(2)O(16)Ϫ2517(4)4678(4)6168(4)82(2)O(17)Ϫ498(4)1993(4)4698(4)89(2)O(18)125(5)3921(5)4556(5)46(2)O(19)Ϫ691(4)5532(4)7437(4)88(2)O(20)Ϫ1199(5)3920(6)4556(5)44(2)O(21)Ϫ517(5)5232(6)4229(5)43(2)O(22)749(5)5233(6)4222(5)42(2)O(23)6355(4)4122(5)9110(4)103(2)O(24)4363(4)3734(5)8075(4)106(2)O(25)2762(4)4125(5)9109(4)104(2)C(1)7533(6)4829(8)9479(6)112(4)C(2)6132(8)3866(8)8117(7)115(2)C(3)4923(6)3101(7)7767(7)112(2)C(4)3166(7)3090(7)7767(7)113(3)C(5)2739(7)3888(7)8102(7)116(3)C(6)2325(6)4882(7)9483(7)118(4)O(10W)50000500010000177(4)Table 3Selected bond lengths (A˚).Symmetry transformations used to generate equivalent atoms:#1,Ϫx ;Ϫy ϩ1;Ϫz ϩ1;#2,Ϫx ϩ1;Ϫy ϩ1;Ϫz ϩ2Mo(1)–O(4) 1.631(5)Mo(1)–O(9) 1.812(6)Mo(1)–O(10) 1.836(5)Mo(1)–O(14)#1 1.948(6)Mo(1)–O(7) 1.961(5)Mo(1)–O(20)#1 2.473(8)Mo(1)–O(21)#1 2.498(6)Mo(2)–O(1) 1.632(5)Mo(2)–O(17) 1.856(6)Mo(2)–O(12) 1.870(6)Mo(2)–O(8)#1 1.967(5)Mo(2)–O(9)#1 1.997(6)Mo(2)–O(20) 2.493(7)Mo(2)–O(18) 2.499(6)Mo(3)–O(2) 1.638(5)Mo(3)–O(16) 1.942(5)Mo(3)–O(14) 1.847(6)Mo(3)–O(12) 1.950(6)Mo(3)–O(13) 1.954(6)Mo(3)–O(20) 2.468(7)Mo(3)–O(22)#1 2.495(6)Mo(4)–O(6) 1.653(6)Mo(4)–O(7) 1.850(4)Mo(4)–O(15)#1 1.875(6)Mo(4)–O(17) 1.948(5)Mo(4)–O(11) 1.956(6)Mo(4)–O(18) 2.457(9)Mo(4)–O(21)#1 2.492(8)Mo(5)–O(3) 1.675(5)Mo(5)–O(11) 1.833(6)Mo(5)–O(13) 1.841(5)Mo(5)–O(10) 1.954(4)Mo(5)–O(19) 1.958(6)Mo(5)–O(22)#1 2.456(8)Mo(5)–O(21)#1 2.469(7)Mo(6)–O(5) 1.642(5)Mo(6)–O(8) 1.831(4)Mo(6)–O(19) 1.835(6)Mo(6)–O(15) 1.937(6)Mo(6)–O(16) 1.963(4)Mo(6)–O(18)#1 2.470(8)Mo(6)–O(22)#1 2.492(8)P–O(21)#1 1.501(8)P–O(21) 1.501(8)P–O(22) 1.513(7)P–O(22)#1 1.513(7)P–O(20)#1 1.525(5)P–O(20) 1.525(5)P–O(18)#1 1.526(7)P–O(18) 1.526(7)O(23)–C(1) 1.393(8)C(23)–C(2) 1.397(11)O(24)–C(3) 1.392(10)O(24)–C(4) 1.399(9)O(25)–C(6) 1.411(10)O(25)–C(5) 1.421(11)C(1)–C(6)#2 1.453(13C(2)–C(3) 1.424(11)C(4)–C(5)1.438(12)C(6)–C(1)#21.453(13)Fig.1.IR spectrum of [C 12H 24O 6][H 3PMo 12O 40]·22H 2O.1,the partial atomic coordinates with standard devia-tions and isotropic atomic displacement parameters are provided in Table 2and the selected bond lengths are listed in Table 3.3.Results and discussionThe title compound was prepared by mixing 18C6and H 3PMo 12O 40in a mixed solvent of CH 3CN and CH 3OH.The product was obtained as yellowish-green crystals with an yield of about 25%.Elemental analysis,IR and NMR data of the compound are consistent with the crystal structure.3.1.IR spectrumThe IR spectrum of the title compound is shown in Fig. 1.The characteristic peaks at 803,880,957,and 1062cm Ϫ1demonstrate that PMo 12O 3Ϫ40is a a -Keggin structure.The peaks at 1600–1100cm Ϫ1are characteristic of 18C6.The stretching mode of H 3O ϩis a very broad band at ϳ2900cm Ϫ1,which overlaps the sharper peaks arising from the C–H stretching motions of the crown ether.The C–O–C stretching vibration of 18C6was observed at 1250cm Ϫ1(s).W.You et al./Journal of Molecular Structure 524(2000)133–139136Fig.2.1H NMR spectrum of [C 12H 24O 6][H 3PMo 12O 40]·22H 2O.Fig.3.Structure of the PMo 12O 3Ϫ40anion.3.2.1H NMR spectrumThe1H NMR spectrum of the title compound isshown in Fig.2.The line at3.743ppm is assignedto CH2of18C6and the line at4.955ppm to H3Oϩand H2O.These data are characteristic of the structureof18C6.3.3.The crystal structureA single crystal X-ray diffraction analysis of thetitle compound showed the compound consisted of18C6,H3Oϩand PMo12O3Ϫ40:The PMo12O3Ϫ40anion shows the same type of crystallographic disorder ashas been found in many crystal structures with Kegginanions,which has been explained by several authors[5,12–14].The central atom P is located at the inver-sion center0,5000,5000(see Table2).It shows thatthe central atom P is surrounded by a cube of eightoxygen atoms,with each oxygen site half-occupied,and the Mo atoms situated at the corners of a regularcubooctahedron(Fig.3).P–O bonds range from1.501(8)–1.526(7)A˚(mean 1.516A˚).The Mo–O t(terminal)bonds are in the usual range of1.631(5)–1.675(5)A˚(mean1.645A˚).The Mo–O(P)bonds arein the range of2.456(8)–2.499(62)A˚(mean2.480A˚).All Mo–Mo distances are nearly equal,rangingfrom 3.5553(11)–3.5696(10)A˚(mean 3.5627A˚).The alternating long and short Mo–O–Mo bonds inall MoO6octahedra fall into two well-resolved cate-gories:the long pairs of Mo–O b(bridge)bonds in therange1.937(6)–1.997(6)A˚(mean1.958A˚)and theshort pairs of Mo–O b bonds in the range1.812(6)–1.875(6)A˚(mean1.844A˚).In the title compound,O10W is referred to asoxonium ion.The oxonium ion plays an importantrole in bonding18C6with PMo12O3Ϫ40:There are interactions between the oxonium ion and the crownether molecule(Fig.4).The oxonium ion is located onthe center of the plane defined by O(23),O(24),O(25),O(23A),O(24A)and O(25A)of the crownether molecule.The oxonium ion bonds with sixoxygen atoms of the crown ether in nearly identicaldistances,O(23,23A), 2.7825(69)A˚;O(24,24A),2.7569(50)A˚;O(25,25A), 2.7919(40)A˚(mean2.7771A˚),which are appreciably shorter thanexpected for the crown ether(2.95A˚)[9].It is difficultto determine which of six oxygen atoms of the crownW.You et al./Journal of Molecular Structure524(2000)133–139137Fig.4.View of the O10W and structure of18-crown-6showing the interactions between them.ether molecule bond with hydrogen atoms of the oxonium ion.This interaction or the hydrogen bonding is electrostatic or resonant,contrary to Behr’s opinion [15].The above-mentioned 1H NMR result,in which the line for ϾCH 2is not split,supports the conclusion.In the unit cell,polyoxometalates and crown ethers are alternatively arranged in good order along c -axis (Fig.5).Water molecules occupy the space left by polyoxometalates and crown ethers.Except O10W,42water molecules are disordered,each with an occu-pancy factor of 0.5.They form hydrogen bonds with each other,but almost not with polyoxometalates and crown ethers.4.ConclusionBy the self-assembly,the supermolecular compound,[C 12H 24O 6][H 3PMo 12O 40]·22H 2O,was synthesized.Itconsists of PMo 12O 3Ϫ40;18C6,oxonium ions andwater molecules.PMo 12O 3Ϫ40possesses a disordered a -Keggin structure.An oxonium ion is located at the center of a crown ether molecule.It is a good example of the interaction between the crown ether and an oxonium ion.Supplementary Data relating to this article are deposited with the B.L.L.D.as Supplementary Publi-cation No.SUP 26637.AcknowledgementsThis project was financially supported by the State Key Laboratory of Coordination Chemistry of Nanjing University of China and the National Science Council of China.We thank Dr Xu Yan for helpful discussion and revision on the crystal structure.W.You et al./Journal of Molecular Structure 524(2000)133–139138Fig.5.Packing diagram viewed down the a -axis for [C 12H 24O 6][H 3PMo 12O 40]·22H 2O.References[1]E.Coronado,C.J.Go´mez-Garcı´a,Chem.Rev.98(1998)273and references therein.[2]E.B.Wang, C.W.Hu,L.Xu,Concise Polyoxmetalates,Chemical Industry,Beijing,1997.[3]J.M.Lehn,Angew.Chem.27(1989)89.[4]X.M.Lu,R.F.Zhang,S.C.Liu,Polyhedron16(1997)3865.[5]R.Neier,C.Trojanowski,R.Mattes,J.Chem.Soc.DaltonTrans.(1995)2521.[6]R.M.Izatt,B.L.Haymore,J.J.Christensen,J.Chem.Soc.mun.(1972)1308.[7]R.Che`nevert, A.Rodrigue,M.Pigeon-Gosselin,Can.J.Chem.60(1982)853.[8]G.S.Heo,R.A.Bartsch,.Chem.47(1982)3557.[9]R.Che`nevert,A.Rodrigue,P.Beauchesne,Can.J.Chem.62(1984)2293.[10]J.P.Behr,P.Dumas,D.Moras,J.Am.Chem.Soc.104(1982)4540.[11]X.Wu,J.Bio.Chem.43(1920)189.[12]J.Peng,E.B.Wang,Y.S.Zhou,J.Chem.Soc.Dalton Trans.(1998)3865.[13]H.T.Evans,M.T.Pope,Inorg.Chem.23(1984)501.[14]P.Le 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Synthesis and Characterization of Alumina Nanoparticles
This article was downloaded by: [Cold and Arid Regions Environmental and Engineering Research Institute] On: 01 April 2014, At: 00:59Publisher: Taylor & FrancisInforma Ltd Registered in England and Wales Registered Number: 1072954 Registered office: Mortimer House, 37-41 Mortimer Street, London W1T 3JH, UKMaterials and Manufacturing ProcessesPublication details, including instructions for authors and subscription information:/loi/lmmp20Synthesis and Characterization of AluminaNanoparticles by Igepal CO-520 Stabilized ReverseMicelle and Sol-Gel ProcessingJ. Chandradass a & Dong-Sik Bae aa School of Nano and Advanced Materials Enginneering , Changwon National University ,Gyeongnam, South KoreaPublished online: 21 Jun 2008.PLEASE SCROLL DOWN FOR ARTICLEMaterials and Manufacturing Processes ,23:494–498,2008Copyright ©Taylor &Francis Group,LLC ISSN:1042-6914print/1532-2475online DOI:10.1080/10426910802104211Synthesis and Characterization of Alumina Nanoparticles by IgepalCO-520Stabilized Reverse Micelle and Sol-Gel ProcessingJ.Chandradass and Dong-Sik BaeSchool of Nano and Advanced Materials Enginneering,Changwon National University,Gyeongnam,South KoreaNanosized alumina powders have been prepared via reverse micelle and sol-gel processing.By stepwise hydrolysis using aqueous ammonia as the precipitant,hydroxide precursor was obtained from nitrate solutions dispersed in the nanosized aqueous domains of microemulsion consisting of cyclohexane as the oil phase,poly(oxyethylene)nonylphenyl ether (Igepal CO-520)as the non-ionic surfactant,and an aqueous solution containing aluminium nitrate as the water phase.The synthesized and calcined powders were characterized by thermogravimetry-differential thermal analysis,transmission electron microscopy,and scanning electron microscopy.The XRD analysis showed that the complete transformation from -Al 2O 3nanocrystalline to -Al 2O 3was observed at 1100 C.The resulting alumina nanopowder exhibits particle agglomerates of 135–200nm in average diameter occur when they calcined at 1200 C.The average particle size was found to increase with increase in water to surfactant (R )molar ratio.Keywords Al 2O 3;Ceramics;Characterization methods;Crystallization;Differential thermal analysis;Microemulsion;Nanopowder;Scanning electron microscopy;Sol-gel processing;Thermogravimetric analysis;Transmission electron microscopy;X-ray diffraction.IntroductionIn recent years,there has been an increasing interest in the synthesis of nanocrystalline metal oxides [1–5].Such nanocrystals are important for a variety of applications including fabrication of metal-ceramic laminate composites and as a reinforcement phase in polymer and brittle matrix composites.Corundum ( -Al 2O 3 is one of the most important ceramics materials.Nanocrystalline -Al 2O 3powder has considerable potential for a wide range of applications including high strength materials,electronic ceramics,and catalyst [6,7].In particular high quality nanocrystals of corundum are used as electronic substrates,bearing in watches and other fine precision equipment [8]. -Al 2O 3powders prepared by conventional methods require high temperatures 1300–1600 C for solid-state thermally driven decomposition of the hydrates of alumina [7].Various methods for synthesizing -Al 2O 3include mechanical milling [9],vapor phase reaction [10],precipitation [11],sol-gel [12],hydrothermal [13],and combustion methods [14].Mechanical synthesis of -Al 2O 3requires extensive mechanical ball milling and easily introduces impurities.Vapor reaction for preparing fine -Al 2O 3powder from a gas phase precursor demands high temperature above 1200 C.The precipitation method suffers from its complexity and time consuming (long washing times and aging time).The direct formation of -Al 2O 3via the hydrothermal method needs high temperature and pressure.The combustion method has been used to yield -Al 2O 3powders,whereas the powder obtained from the process is usually hard aggregated but contains nanosized primary particles.The sol-gel method based on molecularReceived November 11,2007;Accepted March 20,2008Address correspondence to Dong-Sik Bae,School of Nano and Advanced Materials Enginneering,Changwon National University,Gyeongnam 641773,South Korea;Fax:+82-55-262-6486;E-mail:dsbae7@changwon.ac.krprecursors usually makes use of metal alkoxides as raw materials.However,the high prices of alkoxides and long gelation periods limit the application of this method.Among all the chemical processes that were developed for the preparation of fine ceramic powder a wide array of metal and metal oxide compounds [15–17],the microemulsion process involving reverse micelles has been demonstrated as a superior method [18]in terms of being able to deliver homogeneous and nanosized grains of a variety of oxides.A microemulsion system consists of an oil phase,a surfactant,and an aqueous phase.It is thermodynamically stable isotropic dispersion of the aqueous phase in the continuous oil phase [19].The size of the aqueous droplets is in the range of 5–10nm,rendering the microemulsion systems optically transparent.Chemical reactions,such as precipitation,will take place when droplets containing the desirable reactants collide with each other.The group of these aqueous droplets involving the microemulsion system will thus be acting as a nanosized reactor yielding nanosized particles.Recently,reverse micelle and sol-gel processing [20–22]have successfully prepared several important nanosized ceramic powder systems.Many of the processing parameters such as the concentration of inorganic salts in the aqueous phase and water to surfactant ratio R in the microemulsion,affect the characteristics including the particle size,particle size distribution,agglomerate size,and phases of the resulting ceramic powders.The objective of the present study is to investigate the feasibility of preparing ultrafine alumina nanoparticles by combining reverse micelle and sol-gel processing and to study the effect of water to surfactant ratio R .Experimental procedureTypically,microemulsions of total volume 20mL were prepared at ambient temperature in a 30mL vial with rapid stirring:these consisted of 4mL of nonionic surfactant poly(oxyethylene)nonylphenyl ether (Igepal CO-520,Aldrich Chemical Co.,USA),10ml of cyclohexane,494D o w n l o a d e d b y [C o l d a n d A r i d R e g i o n sE n v i r o n m e n t a l a n d E n g i n e e r i n g R e s e a r c h I n s t i t u t e ] a t 00:59 01 A p r i l 2014SYNTHESIS AND CHARACTERIZATION OF ALUMINA NANOPARTICLES 4950.65–1.32mL of 5×10−1M Al(NO 3 2·9H 2O solution (Aldrich Chemical Co.,USA)and deionized water.The size of the resulting particles was controlled by the ratio R =[water]/[surfactant].The microemulsion was mixed rapidly,and after 5minutes of equilibration,one drop (∼0.05ml)of hydrazine hydrate (9M N 2H 4·xH 2O,Aldrich Chemical Co.,USA)was added as a reducing agent.After nanosized water droplets were formed while stirring,NH 4OH (28%)(Dae Jung chemicals,Korea)was injected into the microemulsion.The microemulsion was then centrifuged to extract the particles,which were subsequently washed by ethanol to remove any residual surfactant.The thermal characteristics of alumina precursors were determined by thermogravimetry and differential thermal analysis (TA 5000/SDT 2960DSC Q10).The phase identification of calcined powders was recorded by X-ray diffractometer (Philips X’pert MPD 3040).The size and morphology of the resulting powders were examined by transmission electron microscopy (TEM)and Scanning electron microscopy (SEM).Results and discussionTernary systems of cyclohexane/Igepal CO 520/water offer certain advantages:they are spheroidal and monodisperse aggregates where water is readily solublized in the polar core,forming a “water pool”characterized by the molar ratio of water to surfactant concentration R .Another important property of reverse micelle is their dynamic character;the “water pool”can exchange their contents by collision process.The aggregation and self-assembly of the alumina/surfactant/water species is complex and very little is known about the cluster growth and final nanostructure as a function of synthesis condition.The molar ratio of water to surfactant can determine the size of the micro-emulsion water core [23].Therefore,the R -value can control the diameter of the nanoparticle in the micro-emulsion.The average size of the cluster was found to depend on the micelle size,the nature of the solvent,and the concentration of reagent.During the preparation of alumina nanoparticles,the following reaction might occur.Thermal behavior of the precursor determined by TG-DTA in oxygen up to 1200 C at a heating rate of 10 C/min is shown in Figs.1and 2,respectively.NH 3·H 2O →NH +4+OH (1)OH +Al +3→Al OH 3(2)Al OH 3→Al 2O 3+H 2O(3)In the temperature region between RT-180 C,a broad endothermic peak with a weight loss of 9%is attributed to the adsorption of physisorbed water.In the temperature region between 180–600 C,three exothermic peaks were observed at 208,288,and 390 C with a weight loss of 50%corresponding to the decomposition of organic residuals from the precursor.From the TGA curve it is also observed that the precursor exhibit weight loss at <600 C,and at >600 C the weightbecomesFigure 1.—DTA curve of alumina precursor ramped at 10 C/min in air.almost constant.The peak around 1200 C is attributed totransformation of -Al 2O 3from -Al 2O 3.X-ray diffraction (XRD)analysis of precursor powder calcined at 1000,1100,and 1200 C are shown in Fig.3.Diffraction peaks corresponding to -Al 2O 3and weak peaks of -Al 2O 3have been found for samples calcined at 1000 C for 2h indicating - -Al 2O 3transformation.The difference in the crystallization temperature of -Al 2O 3as observed in DTA and XRD could be because of the difference in heating schedule for the two samples.While XRD pattern was recorded on samples which were held for 2h at 1000 C,the DTA was done without any isothermal hold.Thus the isothermal hold at 1000 C has accelerated the transformation to -Al 2O 3at lower temperature.With the increase of calcinations,temperature to 1100 C -Al 2O 3disappears;only -Al 2O 3with low intensity peaks is found indicating complete transformation to -Al 2O 3.A typical XRD pattern of the resultant -Al 2O 3powders after calcinations at 1200 C (2h)are shown in Fig. 4.The crystalline size of the calcined powders (1200 C)atFigure 2.—TGA curve of alumina precursor ramped at 10 C/min in air.D o w n l o a d e d b y [C o l d a n d A r i d R e g i o n sE n v i r o n m e n t a l a n d E n g i n e e r i n g R e s e a r c h I n s t i t u t e ] a t 00:59 01 A p r i l 2014496J.CHANDRADASS AND D.-S.BAEFigure 3.—XRD patterns of the alumina nanoparticles synthesized at R =4and calcined at different temperatures (a)1000 C;(b)1100 C;(c)1200 C (•- -Al 2O 3; - -Al 2O 3 .different value of R has been obtained from X-ray line broadening studies using the Scherer equation [24].Table 1shows that water/surfactant molar ratio R influenced crystallite size.The crystallite size of the alumina nanoparticles increased with increase in R -value from 4to 8.An increase in the domain size of aqueous droplets,duetoFigure 4.—XRD patterns of the as-synthesized alumina nanoparticles calcined at 1200 C and as a function of R (a)R =4;(b)R =6;(c)R =8.Table 1.—The crystallite size of -Al 2O 3at 1200 C.R =[water]/[surfactant]Crystallite size (nm)481684896Figure 5.—TEM micrographs of as-synthesized alumina nanoparticles calcined at 1200 C and as a function of R (a)R =4;(b)R =6;(c)R =8.D o w n l o a d e d b y [C o l d a n d A r i d R e g i o n sE n v i r o n m e n t a l a n d E n g i n e e r i n g R e s e a r c h I n s t i t u t e ] a t 00:59 01 A p r i l 2014SYNTHESIS AND CHARACTERIZATION OF ALUMINA NANOPARTICLES497Figure 6.—SEM micrographs of as-synthesized alumina nanoparticles calcined at 1200 C and as a function of R (a)R =4;(b)R =6;(c)R =8.an increase in aqueous content in the microemulsion,will lead to an apparent increase in the size of the particle [19].The nucleation and growth of the alumina nanoparticles is likely to be a diffusion-controlled process through interaction between micelles,but it can be influenced by many other factors such as phase behavior and solubility,average occupancy of reacting species in the aqueous pool and the dynamic behavior of the microemulsion [25].The degree of agglomeration is evident in the TEM micrograph (Fig.5)showing average particle size increase from 135to 200nm as the R -value increases from 4to 8.This is also in agreement with the particle size range as observed from SEM (Fig.6).TEM micrographs (Fig.5)also show the alumina solid bridging (necking)links powder particles together between neighbouring particles.The particle size as observed from TEM is larger than that calculated from the Scherer formula.This is because the nanosized precursor particles derived from micro-emulsions have very high surface areas;thus they tend to aggregate together to form particle agglomerates in the calcined ceramic powders [26].ConclusionNanosized -Al 2O 3powders have been prepared via reverse micelle and sol-gel processing.The XRD analysis showed that the complete transformation from -Al 2O 3to -Al 2O 3was observed at 1100 C.The resulting alumina nanopowder exhibits particle agglomerates of 135–200nm in average diameter occur when they calcined at 1200 C.The average particle size was found to increase with increase in water to surfactant R molar 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Synthesis and characterization of ATO SiO2 nanocomposite coating obtained by sol–gel method
Synthesis and characterization of ATO/SiO 2nanocompositecoating obtained by sol–gel methodXiaoChuan Chen *The Key Laboratory of Materials Physics,Institute of Solid State Physics,Chinese Academy of Sciences,Hefei 230031,People’s Republic of ChinaReceived 19June 2004;accepted 20December 2004Available online 11January 2005AbstractA new sol–gel route was developed for synthesizing homogeneous nanocomposite thin film that was composed of Sb-SnO 2(ATO)nanoparticles and silica matrix.TEM studies show that as-prepared composite thin film contains the amorphous silica matrix and ATO nanocrystalline particles that were dispersed homogeneously in silica matrix.The oxalic acid is an excellent dispersant for colloidal stability of ATO aqueous sol at pH b 5.The result of Zeta potential measurement shows that dispersion mechanism comes from the chemisorption of oxalic acid on the surface of ATO nanoparticles.The thermal treatment in reducing atmosphere considerably promotes grain growth of ATO nanoparticles and changes the optical property of ATO/SiO 2nanocomposite thin film.D 2005Elsevier B.V .All rights reserved.Keywords:Sol–gel preparation;Thin films;Nanocomposites;Sb-doped SnO 21.IntroductionTin oxide is a wide band gap nonstoichiometric semi-conductor with a low n-type resistivity [1–3].The resistance can be reduced further by doping Sb,F elements [4,5].F-doped SnO 2(FTO),Sb-doped SnO 2(ATO)conducting thin films not only have high transparency in the visible region but also are good infrared reflecting materials [6,7].ATO thin films have been used in many fields such as heat shielding coating on low-emissivity window for energy saving [8].Fabrication techniques used to deposit ATO thin film include dip coating based on sol–gel method;sputtering and spray pyrolysis.The sol–gel route has several advantages over the other method.It is a low cost and simple process and makes the precise control of doping concentration easier [9,10].In order to improve the scratching abrasive resistance of ATO thin film prepared by sol–gel route [11,12]a novel sol–gel route has been proposed.In this technological process an organic–inorganic hybrid silica sol was used as the pre-cursor of protecting matrix.The ATO functional componentwas homogeneously distributed in a transparent silica matrix.The mixed structure is of benefit to preventing the crack of thin film in drying and annealing process [13].When a composite material containing two oxides with different pho-to index hopes to keep high transmittance in visible light re-gion the second phase component must be dispersed homogeneously into the amorphous matrix at a level of nanometer.In this work a transparent nanocomposite thin film com-posed of ATO and silica was synthesized by the sol–gel route.The sol–gel method includes (a)the synthesis of ATO sol and hybrid organic–inorganic silica sol;(b)mixing of two nanoparticulate sols.A TEM investigation of phase structure in ATO–silica composite gel is reported.The optical proper-ties and crystallizability of composite thin film is discussed.2.Experimental2.1.Preparation of ATO aqueous solAll the chemical reagents used in the synthesis experi-ment were obtained from commercial sources without0167-577X/$-see front matter D 2005Elsevier B.V .All rights reserved.doi:10.1016/j.matlet.2004.12.033*Tel.:+865515591477;fax:+865515591434.E-mail address:chenxiaochuan126@.Materials Letters 59(2005)1239–1242/locate/matletfurther purification.The aqueous ATO sol were prepared by a co-precipitation process from hydrolysis of SnCl4d5H2O and SbCl3,and followed by the peptization of the precipitate. The reaction was performed at room temperature.In the co-precipitation procedure aqueous NH4OH solution was added directly to the mixture solution of SnCl4d5H2O and SbCl3 until the pH of the mixture reach6–8,where pale yellow ATO hydroxide precipitate were produced.Peptization of ATO hydroxide with the aqueous solution containing oxalic acid gives a yellowish transparent sol.Finally ATO sol was heated and refluxed at608C for4h.2.2.Synthesis of hybrid organic–inorganic silica solThe hybrid organic–inorganic silica-based sols were synthesized as follows:First a mixture solution of tetrae-thoxysilane(TEOS),3-glycidoxypropyltrimethoxysilane (GPTS),isopropyl and alcohol in weight ratio1:1:2.5:3.5 was prepared.Then a suitable amount of deionized water (pH=1,by HCl addition)was added to the mixture solution. The mole ratio of TEOS and H2O is about1:6to1:8.The mixed solution was stirred and heated under reflux at808C for16h.The synthesized transparent hybrid silica sol was used as protecting component of nanocomposite thin film.2.3.Preparation of ATO/SiO2nanocomposite thin filmsA transparent functional gelled film was deposited from the mixture sol comprising the hybrid organic–inorganic silica sol and the ATO sol.Deposition was performed on the glass substrate at room temperature by a simple dip coating process.After being dried at room temperature the nano-composite gelled thin film was thermally densified at a temperature up to4008C in a reducing atmosphere containing N2and vapor of alcohol.2.4.InstrumentationThe Zeta potential measurement of the0.5wt.%ATO aqueous sol was carried out with a ZETASIZER3000HS A measuring system(MALVERN).0.1N HNO3was used to adjust the pH of reference ATO sol that does not contain oxalic acid.The X-ray diffractometer(XRD)was used for the structural characterization of the as-dried and thermally densified ATO–SiO2nanocomposite material.The micro-structure feature of nanocomposite gel film and annealed film were observed with a transmission electron microscope (TEM)(type JEM-2010).The sample for TEM study was prepared as follows:A droplet of mixed sol consisting of ATO colloidal sol and hybrid silica sol was dropped on a copper grid covered with organic film,and after solvents were vaporized a nanocomposite thin film was deposited on the copper grid.The chemical composition of annealed nanocomposite thin film was measured using an energy dispersive X-ray analysis system(EDS)equipped with a scanning electron microscope.Optical transmission was determined using a Varian Cary5E spectrophotometer in the wavelength range of300–2500nm.3.Results and discussion3.1.Surface adsorption studiesWhen oxalic acid was added to the ATO suspension the pH of suspension was adjust to2by the ionization of oxalic acid.Peptization with oxalic acid turns slowly the initial turbid ATO suspension into transparent stable sol.If without addition of oxalic acid ATO nanoparticles in the suspension will show aggregating behavior and begin precipitating at pH b5.The experimental result tells us that colloidal stability of ATO sol comes from addition of oxalic acid.Oxalic acid molecule acts as a surface-modifying agent and prevents aggregation of ATO particles.Fig.1shows the result of Zeta potential measurement at different pH level.The date shows that surface of ATO nanoparticles in aqueous sol is positively charged at pH\5without the addition of oxalic acid.The addition of oxalic acid decreases the Zeta potential of surface and changes the surface to a negative charge in the pH range2–4.According to the dissociation constant of oxalic acid the neutral molecules and negatively charged HO–(CO)2–OÀ1ions are predominant components in aqueous solution at2b pH b3.In initial suspension surface of ATO nanoparticles has a charge especially opposing the oxalic acid ions.The electrostatic force generated by the opposing charges will facilitate the ions transport stage of adsorption reaction.Now we assume that markedinteraction Fig.1.Zeta potential of ATO aqueous sol as a function of pH;0.5wt.% ATO content was used.X.C.Chen/Materials Letters59(2005)1239–1242 1240exist between oxalic acid ions and positive surface hydroxylgroups Q Sn–OH 2+or neutral surface hydroxyl groups Q Sn–OH.The oxalic acid ions can be preferentially adsorbed to the surface of ATO nanoparticles by hydrogen bond or Q Sn–O–C bond.The adsorbed ions neutralize surface positive charges and ultimately reverse the surface to a negative Zeta potential.Fig.1shows that the magnitude of negative Zeta potential is not large enough to stabilize the ATO nanoparticle electrostatically in sol.After oxalic acid was added to the suspension the transparent sol is found to remain stable almost infinitely at pH b 4.The only possible explanation is that effective dispersion mechanism comes from a combination of electrostatic and steric repulsion between oxalic acid ions that were adsorbed on surface of different ATO particles.3.2.XRD and EDS studiesFig.2shows XRD spectra of the ATO–silica nano-composite sample.The pattern (a)relates to the nano-composite gel obtained as dried at room temperature and the pattern (a)shows the presence of a very broad diffraction peak attributable only to cassiterite structure.The XRD patterns of nanocomposite samples show little difference between as-dried and thermally densified samples.Theresult indicates that ATO colloidal particles have developed a nanocrystal structure of cassiterite during sol preparation which contains a hydrothermal process at 608C.TheFig.2.XRD pattern of ATO–SiO 2composite gel:(a)as-dried at room temperature;(b)heat-treated at 5008C in air for 1h.Table 1Elemental concentration of ATO/SiO 2nanocomposite thin film Sample Atomic concentration,%V olume ratio,SiO 2/ATO O Si Sn Sb As-dried69.6917.2510.722.351.5Fig.3.Diffraction pattern and TEM image of ATO–SiO 2nanocomposite thin film as-dried at room temperature:(a)ED pattern;(b)TEMimage.Fig.4.Diffraction pattern and TEM image of ATO–SiO 2composite thin film thermal-treated at 3008C in reducing atmosphere for 2h:(a)ED pattern;(b)TEM image.X.C.Chen /Materials Letters 59(2005)1239–12421241hydrothermal process under atmosphere is also an effective method for promoting the crystallization of ATO nano-particles in the aqueous solution [14,15].The element contents in ATO–SiO 2film are shown in Table 1.Measured Si/Sn+Sb atom ratio of sample is about 1.3:1.The SiO 2/ATO volume ratio in the nanocomposite is calculated from the atom ratio and theory density.3.3.TEM and UV–Vis–Nir spectra studiesThe TEM image of as-dried ATO–SiO 2nanocomposite thin film is shown in Fig.3(b).We can observe that ATO nanoparticles are homogeneously dispersed in SiO 2-based amorphous matrix without any evidence of aggregation.ATO grains are found to have a size range of 3–5nm in diameter.Fig.3(a)shows a typical electron diffraction pattern of ATO nanocrystalline grain.Four electron dif-fraction (ED)rings can be indexed to the pattern of ATO with cassiterite structure.The result is in good agreement with XRD analysis.The structural change induced by thermal treatment of ATO thin film has been investigated.Fig.4shows the ED pattern and TEM image taken from ATO–SiO 2nanocomposite thin film which was annealed at 3008C in reducing atmosphere.The contrast morphology in this image shows some large crystal grains with diameter range from 20nm to 25nm.The ED pattern taken from the same sample contains some sharp spots resulting from thelarge crystallites.The observed results indicate that thermal treatment in reducing atmosphere can accelerate grain growth of ATO nanoparticles.The growth of crystal grain was accompanied by the disappearance of grain boundary and increased electrical conductivity and Nir-light reflec-tance of ATO film [1].The optical transmission spectra of ATO thin film deposited on the glass substrate of 1mm thick are shown in Fig.5.A high transmission of 85%is observed in the visible region.The reduction of transmission in the Nir wavelength arises from improved conductivity of nanocrystalline ATO particles that were heat-treated in the reducing atmosphere.4.ConclusionsThe transparent ATO–SiO 2nanocomposite thin films have been prepared successfully by the sol–gel method.The transmission of thin film is rather high in the visible region,range between 85%and 90%as well as the transmission in Nir region has been decreased to 41%.The thermal treatment in reducing atmosphere is an effective method for promoting crystalline grain growth of ATO nanoparticles.The oxalic acid is an excellent dispers-ing agent for ATO nanoparticle in the aqueous solution in pH range 2–4.References[1]G.Frank,E.Kauer,H.Kostlin,Thin Solid Films 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