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4N Baird's rule represented the extension of Hückel's 4N + 2 rule to triplet state systems. In this work we extend the 2(N + 1)(2) Hirsch rule for spherical aromatic species to open-shell spherical compounds and we provide evidence that those spherical species having a same-spin half-filled last energy level with the rest of the levels being fully-filled, i.e., those having 2N(2) + 2N + 1 electrons and S = N + ?, are aromatic. 相似文献
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《Chemical physics letters》1986,124(3):274-278
We have recorded the photoelectron spectra of the gas phase negative ions N2O− and (N2O)2− both of which were prepared in a nozzle ion source. The shift between the maxima of the two spectra is interpreted in terms of the dissociation energy of the dimer ion. 相似文献
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Jackson M. Chitanda J. Wilson Quail Stephen R. Foley 《Journal of organometallic chemistry》2009,694(9-10):1542-1548
Reaction of acetato-bridged dinuclear palladacycles, [Pd(iminoisoindoline)(μ-OAc)]2, with stoichiometric amounts of PR3 (where R = Ph or Cy) resulted in formation of the corresponding mononuclear phosphine-ligated, six-membered palladacycles with the general formula [Pd(iminoisoindoline)(OAc)PR3]. The analogous chloride complexes were synthesized by reaction of [Pd(iminoisoindoline)(μ-OAc)]2 with LiCl in acetone followed by addition of phosphine to afford the monomeric derivatives [Pd(iminoisoindoline)(Cl)PR3]. Representative crystal structures of both types of mononuclear palladacycles confirmed the mononuclear nature of the complexes and showed a trans-arrangement of the phosphine ligand to the heterocyclic imine-nitrogen of the palladacycles. 相似文献
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N2(OH)2光致异构化机理 总被引:1,自引:0,他引:1
偶氮化合物 ,如偶氮芳烃、偶氮冠醚、偶氮环糊精等作为有机光化学开关分子具有重要的应用价值 ,已引起了人们的广泛重视[1] 。这类分子作为光化学开关的基本原理是反式的偶氮化合物在光照射下异构化为顺式构型 ,如下图所示 :长期以来 ,人们对该反应的机理持有两种不同看法[2 ,3] :一是分子平面内按角旋转机制 ,二是绕N =N键旋转的二面角机制。前者受氮上孤对电子的“阻碍” ,而后者将破坏共轭双键 ,显然两种机制在基态都很难发生 ,而如果光激发后发生n→π 或π→π 跃迁 ,则两种机制均有可能发生。本文用量子化学从头算方法研究基态和激… 相似文献
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Dianne D. Ellis Anthony L. Spek 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(2):147-148
The title complex, [V(C7H7N)(C13H23N2Si2)2Cl], consists of a V metal centre coordinated to five N atoms and a Cl− ion in a pseudo-octahedral arrangement. The N atoms of the benzamidinate ligands form two four-membered chelate rings to V, with bite angles of 63.59 (8) and 64.36 (8)°, whilst the fifth N atom is from a p-tolylimido ligand [V—N—C 172.2 (2)°] located cis with respect to the Cl− ion [Cl—V—Nimido 96.96 (8)°]. 相似文献
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在四氢呋喃中合成了Schiff碱配体N,N'-二(2-羟基苄烯)-2-羟基苯甲基二胺(SB)与二阶过渡金属镍、铜、锌的三核或双核配合物;用钠汞齐还原SB得到了其氢化物N,N'-二(2-羟基苄基)-2-羟基苯甲基二胺(HSB),并在乙醇中合成了经与铜的双核配合物。对这些配合物进行了元素分析和热分析,并测定了电导、红外光谱和紫外光谱,确定了分子式,讨论了可能的配位结构。 相似文献
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Samus' N. M. Strelkov E. A. Tsapkov V. I. Gulya A. P. 《Russian Journal of Coordination Chemistry》2004,30(4):275-279
Complexes of lanthanides with N,N-bis(2-hydroxybenzylidene)-2-hydroxyphenylmethanediamine (H3L) were synthesized and investigated by the elemental, IR, magnetochemical, and thermogravimetric methods. Using the data obtained, they were found to have compositions Ln2L2 · nH2O and La2L2 · MCl2 · 4H2O (Ln = La3+, Pr3+, Nd3+, Dy3+, Er3+; M = Cu2+, Co2+, Ni2+; n = 4, 6). Suggestions on their structures were made. In the interval of 20–140°C, these complexes were shown to be high-resistance semiconductors. 相似文献
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本文讨论了用能量梯度法,在用MINDO/3自洽场方法计算得到的位能面上,分別优化得到线型和三员环型重氮甲烷以及这个单分子反应的过渡态的几何构型。研究了体系在过渡态的九种振动模式和反应途径。体系在反应途径上的每一点都保持C_S点群的对称性。轨道相关图表明反应是对称性允许的。 相似文献
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《Chemical physics letters》1985,122(5):489-492
The rate constant for the bimolecular reaction CO + N2O → CO2 + N2 was determined by comparison of calculated infrared emission profiles of CO2 with those observed in shock-tube experiments in the temperature range 1350–2100 K for CO-N2O-He-Ar mixtures. The rate constant was found to be k1 = 3.2 × 1011exp(−85 kJ/RT) cm3 mol−1 s−1. 相似文献
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一氧化氮是奇电子分子,有聚合倾向。N_2O_2是NO在低温下生成的较弱的二聚物,其几何构型可能有以下三种形式(见图1);由于氮原子上孤对电子的排斥作用,分子不能自由绕N—N轴进行内旋转,因此可能有非环的顺式(C_(2v))和反式(C_(2(?)))构象;又由于NO是极性分子,偶极之间相互作用使得矩形(C_(2(?)))结构也是可能的,但根据振动光谱数据知,最稳定的是非环 相似文献
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Zusammenfassung Es wird die Darstellung verschiedener N1-Alkylsulfonyl-N2-butylharnstoffe beschrieben. Diese Substanzen besitzen keine bakteriostatische Wirkung, sind aber ebenso wie die verschiedenen in der Literatur beschriebenen N1-Arylsulfonyl-N2-butylharnstoffe blutzuckersenkend. 相似文献
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An aminophenol ligand, N,N,N'-tri(2-hydroxy-5-methylbenzyl)-l,2-ethanediamine, was prepared through the Marmich reaction, and structurally characterized by NMR, IR, MS and single-crystal X-ray diffract... 相似文献
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Hongsheng Lu Youlin Ma Baogang Wang Zhiyu Huang 《Journal of Dispersion Science and Technology》2017,38(11):1618-1624
Here, we report a CO2 stimulus-responsive system with anionic surfactant sodium oleate (NaOA) and N, N, N′, N′, N″-Pentamethyldipropylenetriamine (PMDPTA). The microstructure transition from spherical micelles to worm-like micelles was confirmed by rheology measurements, dynamic light scattering (DLS), and cryogenic transmission electron microscopy (Cyro-TEM). There were three types of CO2?responsive groups in PMDPTA. However, because of PMDPTA ionization degrees, just one responsive group of PMDPTA could be ionized by CO2 to work with OA?, resulting in structure transformation from spherical micelles to worm-like micelles. Besides, this system could be switchable between low-viscosity fluid and high viscoelastic by CO2/N2. 相似文献