New Molecular Complex of Fullerene C60 with Porphyrin Dimer [FeTPP]2O: Synthesis and Crystal Structure

Abstract

New molecular complex of C₆₀ with covalently linked (Fe^IIITPP)₂O · C₆₀ dimer has been obtained. The complex has isolated packing of fullerenes in which fullerene molecule is embraced in a pocket built by porphyrins. (Fe^IIITPP)₂O preserves its initial geometry in the complex. The Fe···C(C₆₀) contacts are in the 3.239–3.513 Å range indicating the absence of Fe–C₆₀ coordination. This results in the similarity of the EPR spectra of the complex and parent (Fe^IIITPP)₂O.     

Pd插层NbSe2化合物的制备、晶体结构和电学性质研究

通过固相反应法合成一系列插层化合物Pd_xNbSe₂ (x=0~0.17)。它们与2H-NbSe₂相同, 属于六方晶格, 空间群为P6₃/mmc。Pd占据NbSe₂层间的八面体空位。随着Pd含量的增加, 晶格常数c线性增大, 而a几乎不变。X射线单晶衍射结果表明, Pd_0.17NbSe₂的晶格常数为a=b=0.34611(2) nm, c=1.27004(11) nm。每个Pd原子与六个Se原子键合形成[PdSe₆]八面体来连接相邻的Nb-Se层, 使晶体结构变得更加稳定, 从而提高化合物的热稳定性。电学测试表明, 随着Pd含量的增加, Pd_xNbSe₂的剩余电阻比减小。此外, 超导转变温度也随着Pd含量的增加而下降, 说明Pd的引入不利于NbSe₂的超导态。     

Studies on Cobalt(II) Complexes with Benzenesulfonate: Synthesis,Crystal Structure,and Spectroscopic and Magnetic Properties

Two novel transition metal benzenesulfonate complexes with a formula [Co(H₂O)₆][C₇H₅O₃SO₃]₂?2H₂O (1) and Na₄[Co(H₂O)₂ Cl₄][C₇H₅O₃SO₃]₂?4H₂O (2), have been synthesized and characterized by single-crystal X-ray diffraction technique; thermal analysis was done and spectroscopic and magnetic properties were studied. The [Co(H₂O)₆][C₇H₅O₃SO₃]₂?2H₂O (1) complex crystallizes in the triclinic system; however, the (2) complex crystallizes in the monoclinic crystal system with the C2/c space group. Each Co(II) atom in (1) and (2) is octahedrally coordinated. A hydrogen bond links the complex cation and anion, forming one-dimensional hydrogen-bonded supramolecular chains. The complexes exhibit different decomposition characteristics. Magnetic susceptibility measurement shows that complexes have weak anti-ferromagnetic intermolecular interactions between many local spins. The magnitude and nature of these magnetic interactions are discussed in the light of their respective structures, and they are compared with those reported for related systems. Magnetic moments of both compounds at room temperature are characteristic of high-spin complexes Co(II).     

Synthesis, Crystal Structure, and Ionic Conductivity of Tl2Ta2(PO4)2(HP5O16)

Tl₂Ta₂(PO₄)₂(HP₅O₁₆) is synthesized at 400°C in molten polyphosphoric acids containing Tl, Ta, and P in the ratio 4 : 1 : 15, and its crystal structure is determined: monoclinic cell, a = 5.1469 Å, b= 18.451 Å, c = 10.793 Å, = 95.65°, Z = 2, sp. gr. P2₁/m. The framework of the structure is made up of monophosphate and hydrogen pentaphosphate groups which share corners with TaO₆ octahedra. The Tl atoms reside in infinite channels. Neighboring pentaphosphate groups are hydrogen-bonded. In the range 60–350°C, the compound has a rather high ionic conductivity, which is tentatively attributed to proton transport. The activation energy of conduction is 48 ± 1 kJ/mol.     

Synthesis and structure of Bi2CaV2O9

A new compound in the Bi/Ca/V/O system has been found, and its structure determined from single crystal X-ray diffraction data. The new compound, Bi₂CaV₂O₉, is monoclinic with a=7.096(2), b=12.400(2), c=9.397(1) Å, β=107.19(2)°, and Z=4. The two crystallographically distinct VO₄ tetrahedra do not share corners. Thus, there is one oxygen which is not part of a VO₄ tetrahedron, and the structural formula may be written as Bi₂Ca(VO₄)₂O. Mixing of Bi³⁺ and Ca²⁺ occurs on three sites where coordination to oxygen is seven or eight.     

ZnO薄膜的晶体性能的分析

在硅基上制备出了c轴取向高度一致的ZnO薄膜 ,这将有可能成为新型GaN单晶薄膜的过渡层。对ZnO薄膜的晶体性能进行了分析 ,研究不同衬底和不同衬底温度对ZnO薄膜的结晶状况的影响 ,并着重用TEM研究了硅基ZnO薄膜的晶体性能。     

Crystal structure, thermal expansion and electrical properties of a new compound Al0.33DyGe2

A new ternary compound Al_0.33DyGe₂ has been synthesized and studied from 298 K to773 K by means of X-ray powder diffraction technique. The crystal structural refinement of Al_0.33DyGe₂ has been performed by using the Rietveld method. The ternary compound Al_0.33DyGe₂ crystallizes in the orthorhombic of the defect CeNiSi₂-type structure (space group Cmcm, a = 0.41018(2)nm, b = 1.62323(6)nm, c = 0.39463(1)nm, Z = 4 and D_calc = 8.004 g/cm³). The average thermal expansion coefficients α_a, α_b and α_c of Al_0.33DyGe₂ are 1.96 × 10^− 5 K^− 1, 0.93 × 10^− 5 K^− 1 and 1.42 × 10^− 5 K^− 1, respectively. The bulk thermal expansion coefficient α_V is 4.31 × 10^− 5 K^− 1. The resistivity is observed to fall from 387 to 308 µΩ cm between room temperature and 25 K.     

Influence of Deposition Conditions on the Crystal Structure of MoS2 Coating

MoS2 coatings were prepared using an unbalanced bipolar pulsed DC （direct current） magnetron sputtering apparatus under different targets, cathode current densities, power modes and bias voltages. The morphology, structure and growth characteristics of MoS2 coatings were observed and identified respectively by scanning electron microscopy, X-ray diffractometry and mass spectrometry. The results show that MoS2 coatings evolve with the （002） basal plane parallel to the surface by using cold pressed target with lower density, lower cathodic current density, bipolar pulse DC power and minus bias voltage, whereas the coatings deposited under hot pressed target, higher cathodic current density, simple DC power and positive bias voltage have the （002） basal plane perpendicular to the surface. The influence of deposition conditions on the crystal structure of MoS2 coating is implemented by altering its growth rate and the energy of sputtering-deposition particles.     

Li/Ce/La共掺杂对CaBi2Nb2O9陶瓷晶体结构及电学性能的影响

采用固相反应法制备(Li_0.5Ce_0.25La_0.25)_xCa_1-xBi₂Nb₂O₉铋层状结构压电陶瓷, 分析多元稀土元素掺杂对CaBi₂Nb₂O₉(CBN)陶瓷晶体结构、微观形貌及电学性能的影响。Rietveld结构精修表明, 多元稀土元素进入晶格内部形成固溶体, 掺杂使晶体结构有由斜方晶系向四方晶系转变的趋势, 反位缺陷中A位的Bi ³⁺具备6s2孤对电子, 抑制这种变化趋势。SEM照片显示, 掺杂主要抑制晶粒沿垂直c轴平面生长, 这是由于稀土氧化物具备较高的熔点, 在烧结过程中不易扩散。准同型相界附近, 垂直b轴方向的a滑移面被打破, 极化方向沿a轴和b轴, 导致压电性能增强。其中, (Li_0.5Ce_0.25La_0.25)_0.17Ca_0.83Bi₂Nb₂O₉陶瓷具备最优异的性能: 居里温度为913 ℃, 压电系数高达16.4 pC/N; 经850 ℃退火2 h, 其d₃₃值为14.0 pC/N, 约为原始值的85.4%。     

纳米NiAl2O4粉体的制备与表征

采用醇-水共沉淀法制备NiAl2O4纳米粉体,PEG6000作分散剂。通过XRD,TEM及FT-IR等测试手段,研究醇-水比对粉体晶粒度的影响以及PEG6000对NiAl2O4粉体分散性能的影响。结果表明:醇-水的最佳比例为1∶1,此时粉体的晶粒尺寸趋于最小。在沉淀过程中加入PEG6000,可避免前躯体粒子的团聚及粉体在焙烧过程中形成的团聚,改善了粉体的分散性。将制备的NiAl2O4纳米粉体掺合到染料敏化太阳能电池TiO2光阳极中,电池的光电转换效率得到明显的改善。     

Crystal structure and properties of the new complex vanadium oxide K2SrV3O9

The new complex vanadium oxide K₂SrV₃O₉ has been synthesized and investigated by means of X-ray powder diffraction (XPD), electron microscopy and magnetic susceptibility measurements. The oxide has an orthorhombic unit cell with lattice parameters a = 10.1922(2) Å, b = 5.4171(1) Å, c = 16.1425(3) Å, space group Pnma and Z = 4. The crystal structure of K₂SrV₃O₉ has been refined by Rietveld method using X-ray powder diffraction data. The structure contains infinite chains built by V⁴⁺O₅ square pyramids linked to each other via VO₄ tetrahedra. The chains form layers and potassium and strontium cations orderly occupy structural interstices between these layers. Electron diffraction as well as high resolution electron microscopy confirmed the structure solution. Magnetic susceptibility measurements revealed an antiferromagnetic interaction with J of the order of 100 K inside the chains and no long-range magnetic order above 2 K. The origin of the magnetic exchange is likely a result of super-exchange interaction through the two VO₄ tetrahedra linking the polyhedra with the magnetic V⁴⁺ cations.     

Mixed-Cation Cyclohexaphosphates: Synthesis and Crystal Structure of CsCuInP6O18-II

The cyclohexaphosphates CsM²⁺AlP₆O₁₈ (M²⁺ = Ni, Cu, Co, Mn, Cd), CsM²⁺GaP₆O₁₈ (M²⁺ = Ni, Cu, Mn, Cd), CsM²⁺VP₆O₁₈ (M²⁺ = Ni, Co), CsM²⁺FeP₆O₁₈ (M²⁺ = Ni, Cu, Co, Mn), CsM²⁺MnP₆O₁₈ (M²⁺ = Mg, Co), CsM²⁺InP₆O₁₈ (M²⁺ = Ni, Co) (type I), CsCuInP₆O₁₈, CsCuVP₆O₁₈, CsNiMnP₆O₁₈ (type II), Cs₃Cd₃Fe(P₆O₁₈)₂, Cs₃Cu₃Mn(P₆O₁₈)₂, Cs₃Mn₃In(P₆O₁₈)₂, and Cs₃Cd₃In(P₆O₁₈)₂ were prepared by crystallization from molten polyphosphoric acids. The crystal structure of CsCuInP₆O₁₈-II was determined: triclinic cell, sp. gr. P , Z = 1, a= 5.1360 Å, b= 8.917 Å,c = 9.237 Å, = 86.98°, = 75.04°, = 73.53°.     

新型非线性光学晶体MnHg(SCN)4的合成、结构及表征

合成了配合物晶体ＭｎＨｇ（ＳＣＮ）４。用Ｘ射线四确定了此配合物的晶体结构。用元素分析、红外光谱、紫外一可见光谱以及ＴＧ－ＤＴＡ热分析对其进行了化学表征。测量了不同温度下此配事物晶体在纯水中的溶解度。以尿素为标准样品,用１０６４ｎｍ被劝锁模６０ｐｓ脉冲Ｎｄ：ＹＡＧ激光为入射基频光测得此晶体的倍频光强度为尿素的５０倍。因此,ＭｎＨｇ（ＳＣＮ）晶体是一种新的非线性光学材料。