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1.
The corundum-type In(2-2x)Zn(x)Sn(x)O(3) solid solution (cor-ZITO, x ≤ 0.7) was synthesized at 1000 °C under a high pressure of 70 kbar. cor-ZITO is a high-pressure polymorph of the transparent conducting oxide bixbyite-In(2-2x)Zn(x)Sn(x)O(3) (x ≤ 0.4). Analysis of the extended X-ray absorption fine structure suggests that significant face-sharing of Zn and Sn octahedra occurs, as expected for the corundum structure type. In contrast to the ideal corundum structure, however, Zn and Sn are displaced and form oxygen bonds with lengths that are similar to those observed in high-pressure ZnSnO(3). Powder X-ray diffraction patterns of cor-ZITO showed the expected unit cell contraction with increased cosubstitution, but no evidence for ilmenite-type ordering of the substituted Zn and Sn. A qualitative second harmonic generation measurement, for the solid solution x = 0.6 and using 1064 nm radiation, showed that Zn and Sn adopt a polar LiNbO(3)-type arrangement.  相似文献   

2.
A new noncentrosymmetric polar iodate material, ZnIO(3)(OH), has been hydrothermally synthesized as crystals and pure powders by using ZnO (or Zn(CH(3)CO(2))(2)·2H(2)O), HIO(3), and water. Single crystal X-ray diffraction was used to determine the crystal structure of the reported material. ZnIO(3)(OH) exhibits a layered structure that is composed of ZnO(6) and IO(3) polyhedra. Powder nonlinear optical (NLO) properties measurements on ZnIO(3)(OH) using 1064 nm radiation indicate the material has a second-harmonic generating (SHG) efficiency of approximately 20 times that of α-SiO(2). Additional SHG measurements reveal that the material is not phase-matchable (type 1). Infrared spectroscopy, elemental analysis, and thermogravimetric analysis for the reported compound are also presented. Crystal data: ZnIO(3)(OH), monoclinic, space group Cc (no. 9) with a = 4.67670(10) ?, b = 11.2392(4) ?, c = 6.3308(2) ?, β = 90.019(2)°, and Z = 4.  相似文献   

3.
以醋酸锌和氯化锡为原料,以聚甲基丙烯酸钠(PMA)为表面活性剂,利用水热法合成了偏锡酸锌(ZnSnO3)纳米微粒;采用X射线衍射仪、傅立叶变换红外光谱仪、扫描电镜等分析了ZnSnO3纳米微粒的晶相、表面组成、形貌;并测定了ZnSnO3纳米微粒对甲基橙溶液的光催化降解性能.结果表明,所得ZnSnO3纳米微粒粒径约为20nm,表面存在羧基;其对pH=2的甲基橙溶液的光催化降解效果较好,甲基橙的初始浓度越低,降解效果越明显;随着催化剂用量的增加,降解效率逐渐增大.此外,循环催化试验结果表明ZnSnO3纳米微粒具有较好的催化稳定性.  相似文献   

4.
[M(en)3]2Sn2Se6(M=Mn,Zn)的制备及其热稳定性   总被引:4,自引:0,他引:4  
陈震  王如骥 《物理化学学报》1999,15(12):1070-1075
用有机溶剂热生长技术(SolvothermalTechnique)制备过渡金属锰和锌硒化物[Mn(en)3]2Sn2Se6(Ⅰ),[Zn(en)3]2Sn2Se6(Ⅱ).用单晶X射线衍射技术对其进行晶体结构分析.[Zn(en)3]2Sn2Se6样品的热分析结果表明,该化合物的热分解分三步进行.光学性质测试表明它们是半导体材料,[Mn(en)3]2Sn2Se6的能带隙为1.76eV.[Zn(en)3]2Sn2Se6的能带隙为2.49eV.  相似文献   

5.
以7-甲基-2-丙基-3H-苯并[d]咪唑-5-羧酸甲酯为原料,经还原反应和水解反应两步制得配体3-(羧甲基)-7-甲基-2-丙基-3H-苯并咪唑-5-羧酸(MZ);以Zn(NO_3)_2·6H_2O为锌源,MZ经配位反应合成一个新型的锌(Ⅱ)配合物{[Zn(MZ)_2]·2H_2O}_n(3),其结构经~1H NMR,FT-IR,X-射线单晶衍射和元素分析表征。3属单斜晶系,P2/c空间群,晶胞参数a=0.786 42(16)nm,b=1.072 1(2)nm,c=1.725 9(3)nm,α=γ=90°,β=93.63(3)°,V=1.452 2(5)nm3,D_c=1.482 g·cm~(-3),Z=2,R1=0.059 3,wR_2=0.141 5。  相似文献   

6.
C4H8N2H4·Zn(HPO3)2的水热合成和结构表征   总被引:5,自引:5,他引:5  
在过去的十几年中 ,人们对含有机模板的、由 Zn O4 四面体和 PO4 四面体基本结构单元组成的磷酸锌盐进行了深入广泛的研究 ,发现其结构具有多样性 [1] .近年来 ,人们又开始探索用亚磷酸氢根( HPO3)替代磷酸根 ( PO4 ) ,形成结构新颖的含有机模板的亚磷酸盐 .与磷酸根相比 ,亚磷酸氢根只能与 3个邻近的阳离子通过 P— O— M( M=Zn等 )键相连 ,结构同 [PO3( OH) ]相似 .鉴于此 ,HPO3完全可以作为搭建空旷骨架化合物的结构基元 .与磷酸盐的研究相比 ,以有机胺为模板的过渡金属亚磷酸盐合成研究相对较少 .Harrison等 [2 ,3] 报道了通过…  相似文献   

7.
Introduction Boratecompounds,inwhichboronisboundonly tooxygen,areofconsiderablemineralogicalandindus trialimportance.Thesecompoundscontaininganionic componentscomposedofBO3andBO4groups,which maybelinkedtogetherbysharingoxygenatoms,can formisolatedringsand…  相似文献   

8.
DW Lee  DB Bak  SB Kim  J Kim  KM Ok 《Inorganic chemistry》2012,51(14):7844-7850
The solid-state syntheses, crystal structures, and characterization of two stoichiometrically similar quaternary mixed metal selenite and tellurite, In(2)Zn(SeO(3))(4) and Ga(2)Zn(TeO(3))(4), respectively, are reported. While In(2)Zn(SeO(3))(4) crystallizes in the centrosymmetric monoclinic space group P2(1)/n (No. 14) with a = 8.4331(7) ?, b = 4.7819(4) ?, c = 14.6583(13) ?, and β = 101.684(6)°, Ga(2)Zn(TeO(3))(4) crystallizes in the non-centrosymmetric space group I-43d (No. 220) with a = b = c = 10.5794(8) ?. In(2)Zn(SeO(3))(4) exhibits a two-dimensional crystal structure consisting of distorted InO(6) octahedra, ZnO(6) octahedra, and SeO(3) polyhedra. Ga(2)Zn(TeO(3))(4) shows a three-dimensional framework structure that is composed of GaO(4) or ZnO(4) and TeO(3) polyhedra. An effect of the framework flexibility on the space group centricity is discussed. The SHG (second harmonic generation) efficiency of noncentrosymmetric Ga(2)Zn(TeO(3))(4), using 1064 nm radiation, is similar to that of KH(2)PO(4) (KDP) and is not phase-matchable (Type 1). Complete characterizations including infrared spectroscopy and thermal analyses for the reported materials are also presented, as are dipole moment calculations.  相似文献   

9.
传统的微孔晶体材料是以硅酸盐、硅铝酸盐、磷铝酸盐和无机金属磷酸盐等作为结构的骨架[1,2]. 近几年来, 出现了一类新型的无机-有机杂化微孔晶体材料, 这类晶体材料是用刚性和热稳定性较好的有机分子(如芳香多酸和多碱)和金属离子作为骨架的结构单元. 它们能够在去除孔道中的溶剂分子后仍然保持骨架的完整性, 而且其孔道的直径在0.4~1.0 nm之间, 比表面积远大于相似孔道的分子筛. 因此, 这类材料具有许多潜在的特殊性能, 在选择性催化、分子识别和可逆性主客体分子(离子)交换等方面具有诱人的应用前景. Yaghi等[3~11]利用不同的有机分子和各种金属制备出了许多这类晶体材料. 对苯二酸是常见的有机配体, 以它和金属离子为结构骨架所形成的无机-有机杂化微孔晶体有Zn3(BDC)3*(CH3OH),Zn(BDC)*(DMF)(H2O),(TPT)(Py)Cd和Zn4O(BDC)3*(DMF)8(C6H5Cl)等[12~15], 但在对苯二酸与金属构成的骨架中, 由于有多个乙二醇分子配位, 很少形成稳定的三维骨架结构的无机-有机杂化微孔晶体.  相似文献   

10.
Hydrothermal reaction between mixed ligand(1,2,4-triazole and benzoic acid) and Zn(NO3)2·6H2O afforded a three-dimensional(3D) metal-organic framework Zn3(C2H2N3)2(C7H5O2)4(C2H2N3=1,2,4-triazole,C7H5O2=benzoic acid).The compound was crystallized in the hexagonal system with space group R3:a=2.90234(9) nm,b=2.90234(9) nm,c=1.08597(5) nm,γ=120°,V=7.9222(5) nm3,Mr=816.68,Dc=1.541 g/cm3,Z=9,F(000)=3708,R=0.0636,and wR=0.1777.Its structure consists of ZnN2O2 tetrahedron and ZnN2O4 octahedron,which are connected ...  相似文献   

11.
以2,6-吡啶二酸为配体, 与锌盐通过水热合成法得到具有二维网格结构的新型配位聚合物[Zn(PDA)]n(PDA=2,6-吡啶二羧酸根); 采用红外光谱、元素分析、热重分析及单晶X射线衍射等手段对[Zn(PDA)]n的晶体结构进行了表征. 并进一步研究了[Zn(PDA)]n的荧光性质.  相似文献   

12.
Two new noncentrosymmetric (NCS) polar oxide materials, Zn(2)(MoO(4))(AO(3)) (A = Se(4+) or Te(4+)), have been synthesized by hydrothermal and solid-state techniques. Their crystal structures have been determined, and characterization of their functional properties (second-harmonic generation, piezoelectricity, and polarization) has been performed. The isostructural materials exhibit a three-dimensional network consisting of ZnO(4), ZnO(6), MoO(4), and AO(3) polyhedra that share edges and corners. Powder second-harmonic generation (SHG) measurements using 1064 nm radiation indicate the materials exhibit moderate SHG efficiencies of 100 × and 80 × α-SiO(2) for Zn(2)(MoO(4))(SeO(3)) and Zn(2)(MoO(4))(TeO(3)), respectively. Particle size vs SHG efficiency measurements indicate the materials are type 1 non-phase-matchable. Converse piezoelectric measurements resulted in d(33) values of ~14 and ~30 pm/V for Zn(2)(MoO(4))(SeO(3)) and Zn(2)(MoO(4))(TeO(3)), respectively, whereas pyroelectric measurements revealed coefficients of -0.31 and -0.64 μC/m(2) K at 55 °C for Zn(2)(MoO(4))(SeO(3)) and Zn(2)(MoO(4))(TeO(3)), respectively. Frequency-dependent polarization measurements confirmed that all of the materials are nonferroelectric; that is, the macroscopic polarization is not reversible, or "switchable". Infrared, UV-vis, thermogravimetric, and differential thermal analysis measurements were also performed. First-principles density functional theory (DFT) electronic structure calculations were also done. Crystal data: Zn(2)(MoO(4))(SeO(3)), monoclinic, space group P2(1) (No. 4), a = 5.1809(4) ?, b = 8.3238(7) ?, c = 7.1541(6) ?, β = 99.413(1)°, V = 305.2(1) ?(3), Z = 2; Zn(2)(MoO(4))(TeO(3)), monoclinic, space group P2(1) (No. 4), a = 5.178(4) ?, b = 8.409(6) ?, c = 7.241(5) ?, β = 99.351(8)°, V = 311.1(4) ?(3), Z = 2.  相似文献   

13.
ZnSnO3透明导电薄膜:溶胶-凝胶法制备及性能   总被引:1,自引:1,他引:0  
采用溶胶-凝胶(Sol-Gel)过程和旋涂法制备了Zn-Sn-O系统薄膜。通过对干凝胶的热重-差示扫描同步热分析(TG-DSC),研究了干凝胶在烧结过程中的反应历程。采用X射线衍射(XRD)、X射线光电子能谱(XPS)、场发射扫描电镜(FE-SEM)以及紫外-可见透过率(UV-Vis)等表征了烧结后薄膜的晶相、晶格缺陷、微观形貌以及紫外-可见光透过率。本文还研究了烧结温度、N2气氛热处理以及组成变化对薄膜电阻率的影响,结果表明:偏锡酸锌ZnSnO3晶体薄膜具有较低的电阻率;当nZn/(nZn+nSn)=50.3at%时,薄膜的电阻率达极小值,约为8.0×102Ω.cm。偏锡酸锌ZnSnO3晶体的导电机理研究表明:晶格中间隙阳离子含量的增加有利于薄膜电阻率的降低,而氧空位的形成则使其电阻率升高。薄膜的紫外-可见光透过率(UV-Vis)表明:偏锡酸锌ZnSnO3晶体薄膜在400~900 nm的可见光波段透过率可达80%以上。  相似文献   

14.
以Zn(ClO4)2·6H2O, 4,4’-联吡啶及乙酰丙酮(物质的量比1:1:2)在甲醇中通过溶剂热法合成得到了标题聚合物[Zn(acac)2(4,4’-bipy)]n. 经元素分析、红外光谱、核磁共振氢谱、热重及X射线单晶衍射等表征, 其晶体属单斜晶系, P2(1)/c空间群, 晶胞参数: a=1.1366(10) nm, b=1.4914(14) nm, c=1.5534(10) nm, β=132.00(4)°, V=1.957(3) nm3, Z=4. 标题聚合物分子由Zn(acac)2与4,4’-bipy 是以分子比1:1形成一维无限的链状结构. 热重分析结果表明, 聚合物在197 ℃以下稳定性良好. 运用Gaussian 03W对聚合物结构单元进行了量化计算分析, 原子电荷分布及前沿占据轨道组成很好地佐证了晶体结构的配位环境.  相似文献   

15.
A zinc(Ⅱ) complex [(5-(4-nitrophenyl)tetrazolato)2Zn]n was obtained by the hydrothermal treatment of ZnBr2 and NaN3 with 4-nitrobenzonitril in water at 120 ℃ in Pyrex tube. The crystal belongs to orthorhombic system with space group Pbcn, and a=1.040 7(5) nm, b=1.382 1(7) nm, c=2.435 1(13) nm, V=3.503(3) nm3, Z=8. This complex is a good blue fluorescent material in solid state at room temperature. CCDC: 684226.  相似文献   

16.
无机-有机骨架配位聚合物由于在吸附、催化、分离、光学、磁学、主客体化学等功能材料方面具有潜在的应用前景而受到人们的关注[1~5] .这些材料大多是用刚性或柔性的有机配体与d区的金属元素通过较强的配位键或较弱的作用力,如氢键和π-π堆积作用形成1 -D,2 -D,3 -D和笼状结构等多种拓扑结构.选择合适的有机配体不仅可以形成新颖的聚合物结构,同时也可以产生不同的物理性质.Yaghi等[6~10 ] 用对苯二甲酸和均苯三甲酸等芳香多酸有机配体合成出大量的具有孔道开放骨架的配合物.这些配合物在去除孔道中的溶剂后仍然可以保持骨架的完整性,B…  相似文献   

17.
The reaction of 3-ethoxysalicylaldehyde-N,N-bis (3-aminopropyl)methylamine with Zn (Ⅱ) acetate in CH3CH2OH followed by recrystallization in CH3CH2OH gave rise to colourless block crystals of 3-ethoxysalicylaldehyde-N,N-bis(3-aminopropyl)methylamine Zn(Ⅱ). The compound has been characterized by elemental analysis,IR spectrum, molar conductivity and X-ray diffraction structure determination single crystal. It crystallizes in monoclinic, space group P21/c with a=1.028 91(13) nm, b=1.400 35(12) nm, c=1.733 69(19) nm, V=2.476 6(5) nm3, Z=4, Mr=504.91, Dc= 1.354 g. cm-3, T=298(2) K, F(000)= 1 064,μ(Mo Kα)=0.102 7 cm-1, R =0.068 4 and wR =0.185 3for 2 940 observed reflections with I>2σ(Ⅰ). The fluorescence properties of ligand and the complex also have been investigated. The results show that the fluorescence intensity of the Zn(Ⅱ) complex is very stronger than the ligand. In the crystal, the molecules form 1D chain structure by π-π stacking. CCDC: 675010.  相似文献   

18.
采用溶剂热技术合成了一种新型手性配位聚合物[Zn2(C7H8O6)2(bipy)2(H2O)2]·4H2O(C7H8O6=2,3-氧-异丙叉基-L-酒石酸根, bipy=4,4'-联吡啶), 并通过单晶X射线衍射结构分析、元素分析、热重分析以及红外光谱进行了表征. 结构分析数据表明, 该化合物属单斜晶系, C2空间群, 晶胞参数a=2.02334(14) nm, b=1.13896(4) nm, c=1.01094(6) nm, β=117.366(3)°, V=2.0689(2) nm3. 两个晶体学独立的Zn原子均为八面体构型, 其中Zn1原子赤道配位点被2个酒石酸根中的4个羧酸根氧螯合配位, 2个酒石酸根中剩下的4个羧酸根氧中的2个分别与2个Zn2原子连接形成无限一维链, Zn2原子的另外2个反式赤道配位点被2个水分子氧占据, 同时这两种Zn原子的轴向配位点均被4,4'-联吡啶的氮原子占据, 形成具有矩形格子[0.51165(3) nm×1.13896(5) nm]的二维层状结构, 游离的2个水分子通过氢键作用形成二聚体, 并与酒石酸根中未与Zn配位的羧酸氧连接, 把二维层状结构连接成三维网状的超分子结构.  相似文献   

19.
发光配合物1,2-二(2-吡啶甲酰胺基)苯锌的研究   总被引:6,自引:0,他引:6  
合成了发光配合物1,2-二(2-吡啶甲酰胺基)苯锌(1)及其双分子-4,4'-联吡啶复合物(2).用X射线单晶衍射分析方法得到了配合物2的单晶结构.该晶体属三斜晶系,P1空间群,晶胞参数为a=0.96251(6)nm,b=1.50122(9)nm,c=1.64252(12)nm,α=106.958(2)°,β=105.362(3)°,γ=102.978(2)°,V=2.0685(2)nm3,Z=2,Dc=1.563g/cm3,F(000)=1000,R1=0.0367,wR2=0.0898.研究表明,晶体2由1个4,4'-联吡啶通过配位键连接2个化合物1分子构成.晶体2是由沿晶体学b和c轴方向的一维分子柱堆积而成.考察了配合物1的发光性质,配合物1可作为发光材料效率很高的电致发光器件制备.  相似文献   

20.
A series of compounds has been discovered while investigating reactions of rare earth, transition metals, and Ge in excess indium. These compounds, RE2Zn3Ge6 (RE = La, Ce, Pr, Nd), are isostructural, crystallizing in the orthorhombic space group Cmcm with lattice parameters a = 5.9691(9) angstroms, b = 24.987(4) angstroms, and c = 5.9575(9) angstroms for La2Zn3Ge6, a = 5.9503(5) angstroms, b = 24.761(2) angstroms, and c = 5.9477(5) angstroms for the Ce analogue, a =5.938(2) angstroms, b = 24.708(8) angstroms, and c = 5.936(2) angstroms for Pr2Zn3Ge6, and a = 5.9094(7) angstroms, b = 24.619(3) angstroms, and c = 5.9063(5) angstroms for the Nd analogue. The structure is composed of PbO-like ZnGe layers and ZnGe4 cage layers and is related to the Ce4Zn8Ge(11-x) structure type. The bonding in the system can be rationalized using the Zintl concept resulting in a material that is expected to be a valence precise semiconductor, although its behavior is more consistent with it being a semimetal, making it an intermediate case. The results of band structure calculations and magnetic measurements of these compounds are discussed.  相似文献   

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