1-[4-(二甲氨基)苯亚甲基氨基]-4-苯基硫脲的合成及手性晶体结构

对二甲氨基苯甲醛和苯基氨基硫脲缩合反应生成对二甲氨基苯甲醛缩氨基苯硫脲{1-[4-(dimethylamino)ben- zylidene]-4-phenylthiosemicarbazide}, 并从溶液中析出手性晶体. 元素分析、红外光谱、紫外光谱、核磁谱、质谱和X射线衍射测定其组成和结构. 晶体属正交晶系, P2₁2₁2₁空间群, a＝0.77038(14) nm, b＝1.1428(2) nm, c＝1.6726(3) nm, V＝1.4726(5) nm³, Z＝4, D_c＝1.346 g/cm³, F(000)＝632, μ＝0.219 mm^－1, 可观测点精修最终偏离因子: R＝0.0407, wR＝0.1157. 化合物的晶体结构和固态圆二色谱表明化合物在结晶过程中发生单一对映体的手性堆积.     

C60离子束撞击固体表面的坍塌与沉积(II)扫描隧道显微研究

Mass-selected C60 beam produced by laser ablation was accelerated and bombarded the (0001) surface of highly oriented pyrolitic graphite and (111) surface of gold single crystal. The samples were characterized by STM. The STM images showed that, the deposited species collapsed and formed planar structure on the solid surface, but the collapsed species were not dissociated and well oriented on the surface. Both positive and negative C60 ions were observed in the desorption mass spectra, confirming that the species collapsed on the solid surface are still the C60 clusters.     

MOLECULAR AND CRYSTAL STRUCTURE OF （（C6H5）3P）2Ag（CO2H）

<正> C_37 H_31 O_2P_2Ag, Mr = 677. 47. The crystal structure belongs to mon-oclicnic system with space group Cc. Cell constants a =24. 952(2), b = 9. 179(1), c = 15. 262(1) A ,β= 116. 34 (2)°, V= 3132. 9 (3) A3, Z = 4, Dc = 1. 436g/cm3, D0 = 1. 43g/cm3.The final R achieved is 0. 052 for 5677 observed reflections, F (000) = 673. Like other silver complexes, Ag ( I ) in the center of the complex is 4-coordinat-ed. Formic acid anion also acts as a bidentate ligand in this complex beside two triph-enylphosphine groups.     

C_πB~-的激光等离子体产生与质谱分析

随着“足球烃”C_(60)及其他“球碳烃”的发现,以及对它们奇妙的结构与化学行为的不断揭示,碳原子簇的产生与研究已成为当前化学界的一个热门课题.Smalley等最近又将C_(60)中的一个碳原子以硼原子取代,成为Lewis酸,使这方面的研究更加深入。近二年来,我们在自制的装置上对碳原子簇的结构作了较为充分的研究后,又以独特的方式产生了链状构型的C_nB~-,记录了它们的负离子质谱。     

富勒烯聚合物的分子模型预测

采用分子图形软件编辑设计出Ｃ６０的可能聚合构型（Ｃ１１８，Ｃ１２８，Ｃ１３８，Ｃ１７８及Ｔｄ，Ｄ６ｄ，Ｄ５ｄ和Ｄ２ｄ点群的Ｃ１２０分子），对它们进行分子力学优化，并计算出Ｃ１２０分子的各种聚合形式力学能量值，从中可看出以单链连接的哑铃状结构的Ｃ６０二聚体稳定存在的可能性很少。而经离解重组的笼状结构体系能量较低，文章还进一步讨论并描绘了Ｃ６０聚合过程中可能经历的结构重组过程与机理。     

C_(90-150)~+的质谱与结构分析

近年来,随着Smalley等发现C_(60),根据其在质谱中的突出信号强度推论它具有足球形的完美空心构型,并进而认为所有n>30的碳原子簇都具有由五边形和六边形构成的多面体封闭构型以来,对碳原子簇结构的兴趣、认识与研究都发展得很快。然而,目前的研究手段仍以质谱为主,而且基本上局限于n≤80的碳原子簇,对于更高核的碳原子簇的几何构型,还仅限于理论推测。     

双核银配合物Ag_2[Ph_2P(CH_2)_2Ph_2]_4(NO_3·CH_3OH)_2的合成和分子结构研究

dppe配体按文献所示方法自行合成。在10ml甲醇中先后溶入0.05g(0.29mmol)AgNO_3和0.23g(0.58mmol)dppe。将过滤后的清液半敞开静置14天,即析出棱形无色晶体,再以甲醇重结晶。晶体由于溶剂化而极易风化成白色粉末。     

纳米金刚石球晶的激光溅射产生

以脉冲激光束溅射浸入水中的单质碳样品.观察到产生一种外形完美且具有金刚石结构的纳米碳球.研究中考察了处于固/液界面的各种碳源在脉冲激光作用下发生的变化,初步探讨纳米碳球的形成原因.研究结果揭示:对于表面悬挂键为其他基团所饱和的纳米碳粒,金刚石与石墨结构的热力学稳定性相近,并且当熔融碳的尺寸小至纳米级时,其表面张力能产生较高的压力,因此使它同样有可能凝聚成金刚石的结构.     

膦桥多核银络合物[Ag4(dppe)3(NO3)4]的合成与结构

A new polynuclear silver complex with bridging diphorsphine ligand has been synthesized and characterized by :single cryatsl X-ray diffraction method The compound crystallizes in the triclinic space group P1 with a=1.27489, b=1.34715, c=1.47015 nm; α=59.747, β=63.949, γ=70.196°; V=1.9369 nm. The simplest formularis [Ag_4· dppe)_3(NO_3)_4], Mr=1874.79, D_c=1.607 g·cm~(-3), Dm=1.62 g·cm~(-3), μ(MoKa)=11.69 cm~(-1), F(OOO)=942. The structure was solved by conventional heavy-atom techniques and refined by full-matrix least squares to give discrepany indices of R=0.048 and RW=0.060(W=1/[σ(Fo)~2+(PWT*Fo)~2+QWT]-Fo) for 5052 reflections. An empirical absorption correction program DIFABS was performed.Silver atoms are linked by bridging ligands of dppe and nitrate, forming a network extending in space. Each structural unit contains two binuclear subunits, of which silver atoms are bridged by nitrates. The two subunits are connected by one dppe ligand. Silver atoms are not equivalent in subunit and one of the nitrates functions not only as a monodentate bridging ligand, but also as an asymmetric bidentate chelating lingand. All coordinate configurations of silver are shown as distorted tetrahedron.     

碳环管的发现与生长机理初探

C60笼状结构的发现，极大地丰富了碳的结构化学，在进一步的研究中又发现了碳纳米管、“巴基葱”等新的结构形式．Chernozatonskil等还研究了碳环管（Tori）的独特结构，并预测其具有特别的电磁性质［1］．最近，我们在实验中观察到了可能具有这种结构的样品的透射电镜（TEM）图像，并由此探讨了它们的生长机理．样品的制备采用电弧法制C60的装置［2］，但是在纯氮气氛中进行，且在作为阳极的石墨棒外缘裹上一层铝箔，实验采用直流电弧，腔内氮气压力75kPa．放电结束后收集阴极碳棒上的沉积物与腔内的烟灰，研磨成细粉后，在稀盐酸中充…