A New Hydroxo‐bridged Chromium(III) Dimer [Cr(saltn)OH]2·4H2O: Synthesis,Crystal Structure and Magnetic Properties

A new hydroxo‐bridged dimeric Cr(III) complex [Cr(saltn)OH]₂·4H₂O [H₂saltn=N,N′‐bis(salicylidene)trimethylenediamine] has been synthesized and its structural and magnetic properties have been investigated. The complex crystallizes in the triclinic space group P‐1 with one dimeric formula unit in a cell of dimensions a=0.95828(19) nm, b=0.95926(19) nm, c=1.0437(2) nm, α=86.77(3)°, β=82.48(3)°, and γ=64.93(3)°. The geometry around each chromium(III) center is six‐coordinate, distorted‐octahedral. The bridging Cr₂O₂ unit is strictly planar, as required by the crystallographic symmetry. The Cr? O? Cr′ bridging angle is 99.94(16)°, and the distance between Cr…Cr′ is 0.3019 nm. The magnetic susceptibility of the complex has been examined in the range of 2‐300 K. By using the spin‐spin coupled model for an S₁=S₂=3/2 dimeric system , the magnetic data were fitted to give the parameters of g=2.01(1), J=‐0.85(2) cm^‐1, and zJ' =0.18(3)cm^‐1, indicating the presence of a weak antiferromagnetic spin‐exchange interaction between the Cr(III) ions in the binuclear complex.     

加氢脱氮催化剂中硫化钼结构的表征

众所周知,重油加氢脱氮(HDN)所用Mo-Ni/Al2O3催化剂需经预硫化后始有显著的活性,关于硫化的条件工业上已较成熟,但在持续反应过程中硫化催化剂的结构与活性间的关系则很复杂,如硫化钼的价态和结构、金属组分和担体间的相互作用、反应条件及原料对催化剂组分的影响,以及硫化态催化剂中MoS2结晶的形貌等都可以引起催化剂活性本质的变化.     

Synthesis,crystal structure and magnetic properties of a series of polymeric lanthanoid–copper complexes [Ln2Cu3{O(CH2−CO2)2}6]·nH2O (Ln=La,Nd, n=9; Ln=Er,n=6)

The reaction of diglycolic acid, O(CH2CO2H)2, with Cu(NO3)2·2H2O and lanthanoid nitrate hydrate produces a series of novel Ln–Cu mixed metal complexes, [Ln2Cu3{O(CH2CO2)2}6]·nH2O (Ln=La, Nd, n=9; Ln=Er, n=6), which have been characterized by elemental analysis, i.r. spectroscopy, magnetic measurements and X-ray crystallography. The Ln3+ and Cu2+ ions are connected by the carboxylate groups of the ligands, resulting in the formation of a complicated network.     

Me[14]-N4大环四烯镍(Ⅱ)催化、BrO3-氧化丙酮酸的振荡化学反

本文报道了一种以２，３，９，１０－四甲基－１，４，８，１１－四氮杂环十四－１，３，８，１０－四烯镍（Ⅱ）配合物［Ｎｉ（ㄔＩＭ）］＾２＋为催化剂、ＮａＢｒＯ３为氧化剂、丙酮酸为有机废物、稀硫酸为介质的振荡化学反应新体系。对该体系的振荡特性进行了描述。研究了Ａｇ＾＋、Ｈｇ＾２＋、还原性物质、自由基抑制剂、四氯化碳以及温度对振荡的影响。     

Transparent conducting oxides: texture and microstructure effects on charge carrier mobility in MOCVD-derived CdO thin films grown with a thermally stable, low-melting precursor

A series of low-melting, thermally stable cadmium metal-organic chemical vapor deposition (MOCVD) precursors have been synthesized, structurally and spectroscopically characterized, and implemented in growth of highly conductive and transparent CdO thin films. One member of the series, bis(1,1,1,5,5,5-hexafluoro-2,4-pentanedionato)(N,N-diethyl-N',N'-dimethyl-ethylenediamine)cadmium(II), Cd(hfa)(2)()(N,N-DE-N',N'-DMEDA), represents a particularly significant improvement over previously available Cd precursors, owing to the low melting point and robust thermal stability. High-quality CdO films were grown by MOCVD on glass and single-crystal MgO(100) between 300 and 412 degrees C. Film growth parameters and substrate surface have large effects on microstructure and electron carrier transport properties. Enhanced mobilities observed for highly biaxially textured films grown on MgO(100) vs glass are attributed, on the basis of DC charge transport and microstructure analysis, to a reduction in neutral impurity scattering and/or to a more densely packed grain microstructure. Although single-grained films grown on MgO(100) exhibit greater mobilities than analogues with discrete approximately 100 nm grains and similar texture, this effect is attributed, on the basis of charge transport and Hall effect measurements as well as optical reflectivity analysis, to differences in carrier concentration rather than to reduced grain boundary scattering. Unprecedented conductivities and mobilities as high as 11,000 S/cm and 307 cm(2)/V.s, respectively, are obtained for epitaxial single-grained films (X-ray diffraction parameters: fwhm(omega) = 0.30 degrees, fwhm(phi) = 0.27 degrees ) grown in situ on MgO(100) at a relatively low temperature (400 degrees C).     

2, 2＇─(1, 4─亚乙二氧基)—二苯甲酸与钴(Ⅱ)生成的两种配合物的结构研究

硝酸钴与２，２＇－（１，４－亚乙二氧基）－二苯甲酸（Ｈ２Ｌ，图１）作用分别得到红色配合物ＣｏＬ＇和蓝色配合物ＣｏＬ″。经元素分析、红外光谱、紫外可见光谱、热分析等方法进行了表征、ＣｏＬ＇配合物的分子式为［ＣｏＬ．Ｈ２Ｏ］．３Ｈ２Ｏ，近八面体构型，羧酸根以双齿形式与Ｃｏ（Ⅱ）螯合；ＣｏＬ″配合物分子式为［ＣｏＬ″］。Ｈ２Ｏ，近四面体构型，羧酸根以单齿形与Ｃｏ（Ⅱ）配位。     

硝酸镧与冠醚(2, 2)配合物的晶体及电子结构研究

用X-射线单晶衍射法测定了硝酸镧与冠醚(2,2)配合物的晶体结构,发现其具有与报道的Eu(NO_3)_3(2,2)配合物不同的配位方式.晶体属于三斜晶系,空间群P(?),晶胞参数为a=10.312(2)(?);b=12.745(3)(?);c=8.917(2)(?);α=103.79(2)°;β=112.73(2)°;γ=83.68(2)°;V=1049.5(5)(?)~3;F(000)=587.88;Z=2.结构用重原子法解出;R值为0.0292.用INDO法计算了配合物的净电荷分布,电子结构、键级.结果表明,镧与配位原子间的键具有一定程度的共价性.镧的5d轨道对共价性的贡献最大,而4f轨道基本上不参与成键.La-N比La-O(醚)间存在较强的作用,增大了配合物的稳定性.     

钼体系催化丁二烯聚合动力学——链转移

本文考察了MoCl_4OC_8H_(17)-(i-Bu)_2Alo催化体系在加氢汽油中催化丁二烯聚合过程中的链转移情况,提出了比较聚合体系中各组分对链转移的贡献大小的方法和计算链转移次数的公式及链转移次数与聚合温度的函数关系式。发现本体系中单体和主催化剂是主要的链转移剂,向烷基铝的链转移占10％,向杂质的链转移仅占6％。在链转移反应中,单体和主催化剂的级数为1,烷基铝的级数为1/2。     

聚噻吩的固相聚合及其应用

作为共轭聚合物的典型代表,因聚噻吩衍生物具有良好的稳定性和结构易改性,其在有机光电子领域、新能源等有重要的应用。而固相聚合作为一种环保、可大规模制备等优点,受到研究者的关注。本文主要总结了近年来聚噻吩及其衍生物的固相聚合反应单体分子设计、聚合研究机理以及相关应用的进展,并展望了未来的研究方向。     

PdH2、YH2分子的结构与势能函数

用密度泛函理论的B3LYP方法,对钯和钇原子采用SDD收缩价基函数,氢原子采用6-311＋＋G**全电子基函数,对PdH2和YH2体系的结构进行优化计算,得到PdH2分子最稳态为C2v构型,电子组态为1A1,平衡核间距RPdH=0.1692 nm,键角∠HPdH=29.4°,离解能De=5.5212 eV,基态简正振动频率:ν1(b2)=1470.1 cm－1、ν2(a1)=1007.9 cm－1、ν3(a1)=2907.0 cm－1.YH2分子最稳态也为C2v构型,电子组态2A1,RYH=0.1962 nm,∠HYH=114.3°,De=5.6691 eV,基态简正振动频率:ν1(b2)=1457.9 cm－1、ν2(a1)=476.0 cm－1、ν3(a1)=1506.3 cm－1.由微观过程的可逆性原理分析了分子的可能离解极限.并用多体项展式理论方法分别导出基态PdH2和YH2分子的势能函数,其等值势能面图准确地再现了PdH2和YH2分子的结构特征和离解能,由此讨论了Pd ＋ H2和Y ＋ H2分子反应的势能面静态特征.