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61.
利用2,3-二(2'-氰乙基硫基)-6,7-二烷硫基四硫富瓦烯在甲醇钠的作用下消除一个保护基团生成四硫富瓦烯单钠盐,与1,4-二(氯甲基)苯反应,形成单桥-双(四硫富瓦烯)衍生物,生成的单桥-双(四硫富瓦烯)衍生物再次在甲醇钠的作用下消除剩下的保护基团,形成单桥-双(四硫富瓦烯)衍生物二钠盐,最后与四(3'-碘丙硫基)四硫富瓦烯反应形成新型I型五聚TTF衍生物,并通过循环伏安法和化学氧化法分别对其氧化还原性质和紫外光谱进行了研究. 相似文献
62.
在室温下,以丙酮为溶剂,三氟甲基磺酸银与4,5-二甲硫基-1,3-二硫代环戊烯-2-硫酮(C5H6S5)反应得到一个二维配位聚合物[Ag(C5H6S5)].CF3SO3.(CH3)2CO(1).单晶采用惰性溶剂扩散法培养.X-ray单晶衍射分析表明,1属于正交晶系,P212121空间群,晶胞参数:a=0.825 7(5)nm,b=0.972 1(6)nm,c=2.143(1)nm,V=1.720(1)nm3.在1中一个银离子与不同配体的三个硫原子配位,同时一个配体的两个硫原子参与和银离子配位,形成二维阶梯结构,在二维聚合物分子内存在较强的S…S相互作用,聚合物室温电导率为3.95×10-7S.cm-1,属于半导体.经过碘掺杂后化合物的电导率达到6.80×10-7S.cm-1. 相似文献
63.
《Chemphyschem》2003,4(12):1335-1339
This article describes two‐terminal molecular switch tunnel junctions (MSTJs) which incorporate a semiconducting, single‐walled carbon nanotube (SWNT) as the bottom electrode. The nanotube interacts noncovalently with a monolayer of bistable, nondegenerate [2]catenane tetracations, self‐organized by their supporting amphiphilic dimyristoylphosphatidyl anions which shield the mechanically switchable tetracations from a two‐micrometer wide metallic top electrode. The resulting 0.002 μm2 area tunnel junction addresses a nanometer wide row of ≈2000 molecules. Active and remnant current–voltage measurements demonstrated that these devices can be reconfigurably switched and repeatedly cycled between high and low current states under ambient conditions. Control compounds, including a degenerate [2]catenane, were explored in support of the mechanical origin of the switching signature. These SWNT‐based MSTJs operate like previously reported silicon‐based MSTJs, but differently from similar devices incorporating bottom metal electrodes. The relevance of these results with respect to the choice of electrode materials for molecular electronics devices is discussed. 相似文献
64.
O. A. D'yachenko S. V. Konovalikhin G. V. Shilov R. N. Lyubovskaya M. Z. Aldoshina R. B. Lyubovskii 《Russian Chemical Bulletin》1995,44(5):878-882
On the basis of completely deuterated bis(ethylenedithio)tetrathiafulvalene (d8-ET), new organic conductors, (d8-ET)4[Hg2(SCN)4Cl2] and (d8-ET)2[Hg(SCN)2Br] have been synthesized and studied by X-ray structural analysis. Unlike nondeuterated organic metalsk-(ET)2[Hg(SCN)3–n
X
n
] (X = Cl or Br;n=1 and 2), the crystal structure of (d8-ET)4[Hg2(SCN)4Cl4] exhibits -type packing of the d8-ET radical cations in the conducting layer and a polymeric structure of anions, in which both the SCN groups and the Cl atoms are involved in the bridging bonds. The crystals of (d8-ET)2[Hg(SCN)2Br] and the nondeuterated form (ET)2[Hg(SCN)2Br] are isostructural.Translated fromIzvestiya Akademii Nauk. Seriya Khlmicheskaya, No. 5, pp. 905–909, May, 1995.This work was financially supported by the International Science Foundation (Grant RE1 000), the Scientific Council on the Problems of High-Temperature Superconductivity (Project No. 93030), and the Russian Foundation for Basic Research (Project No. 94-03-09950). 相似文献
65.
66.
Guldi DM Giacalone F de la Torre G Segura JL Martín N 《Chemistry (Weinheim an der Bergstrasse, Germany)》2005,11(24):7199-7210
Two triads (donor-spacer-acceptor), exTTF-BN-C60 (6) and ZnP-BN-C60 (7), in which electron donors (i.e., exTTF or ZnP) are covalently linked to C60 through a chiral binaphthyl bridge (BN), have been prepared in a multistep synthetic procedure starting from a highly soluble enantiomerically pure binaphthyl building block (1). Unlike other oligomeric bridges, with binaphthyl bridges, the conjugation between the donor and the acceptor units is broken and geometric conformational changes are facilitated. Consequently, distances and electronic interactions between the donor and C60 are drastically changed. Both donor-spacer-acceptor (D-s-A) systems (i.e., 6 and 7) exhibit redox processes that correspond to all three constituent electroactive units, namely, donor, BN, and C60. Appreciable differences were, however, observed when comparing triad 6, in which no significant exTTF-C60 interactions were noted, with D-s-A 7, whose geometry favors donor-acceptor and pi-pi interactions that result in ZnP-C60 electronic communication. This through-space interaction is, for example, reflected in the redox potentials. Excited-state studies, carried out by fluorescence and transient absorption spectroscopy, also support through-space rather than through-bond interactions. Although both triads form the corresponding radical-ion pair, that is, exTTF*+-BN-C60*- and ZnP*+-BN-C60*-, dramatic differences were found in their lifetimes: 165 micros and 730 ns, respectively. 相似文献
67.
68.
Pointillart F Le Gal Y Golhen S Cador O Ouahab L 《Chemistry (Weinheim an der Bergstrasse, Germany)》2011,17(37):10397-10404
The reactions between the [Ln(tta)(3)]·2H(2)O precursors (tta(-)=2-thenoyltrifluoroacetonate anion) and the tetrathiafulvalene-3-pyridine-N-oxide ligands (L(1)) lead to dinuclear complexes of formula [{Ln(tta)(3)(L(1))}(2)]·xCH(2)Cl(2) (x=0.5 for Ln=Dy(III) (1) and x=0 for Ln=Gd(III) (2)). The crystal structure reveals that two {Ln(tta)(3)} moieties are bridged by two donors through the nitroxide groups. The Dy(III) centre adopts a distorted square antiprismatic oxygenated polyhedron structure. The antiferromagnetic nature of the exchange interaction between the two Dy(III) ions has been determined by two methods: 1) an empirical method using the [Dy(hfac)(3)(L(2))(2)] mononuclear complex as a model (3) (hfac(-)=1,1,1,5,5,5-hexafluoroacetylacetonate anion, L(2)=tetrathiafulvaleneamido-2-pyridine-N-oxide ligand), and 2) assuming an Ising model for the Dy(III) ion giving an exchange energy of -2.30 cm(-1), g=19.2 in the temperature range of 2-10 K. The antiferromagnetic interactions have been confirmed by a quantitative determination of J for the isotropic Gd(III) derivative (J=-0.031 cm(-1), g=2.003). Compound 1 displays a slow magnetisation relaxation without applied external magnetic fields. Alternating current susceptibility shows a thermally activated behaviour with pre-exponential factors of 5.48(4)×10(-7) s and an energy barrier of 87(1) K. The application of an external field of 1.6 kOe compensates the antiferromagnetic interactions and opens a new quantum tunnelling path. 相似文献
69.
Chiang PT Chen NC Lai CC Chiu SH 《Chemistry (Weinheim an der Bergstrasse, Germany)》2008,14(21):6546-6552
We have observed the mixed-valence and radical cation dimer states of a glycoluril-based molecular clip with tetrathiafulvalene (TTF) sidewalls at low concentration (1 mM) at room temperature. This molecular clip has four consecutive anodic steps in its cyclic voltammogram, which suggests a sequential oxidation of these TTF sidewalls to generate species existing in several distinct charge states: neutral monomers, mixed-valence dimers, radical cation dimers, and fully oxidized tetracationic monomers. The observation of characteristic NIR spectroscopic absorption bands at approximately 1650 and 830 nm in spectroelectrochemistry experiments supports the presence of intermediary mixed-valence and radical cation dimers, respectively, during the oxidation process. The stacking of four TTF radical cations in the dimer led to the appearance of a charge-transfer band at approximately 946 nm. Nanoelectrospray ionization mass spectrometry was used to verify the tricationic state and confirm the existence of other different charged dimers during the oxidation of the molecular clip. 相似文献
70.
S. V. Konovalikhin G. V. Shilov O. A. D'yachenko R. N. Lyubovskaya M. Z. Aldoshina R. B. Lyubovskii 《Russian Chemical Bulletin》1992,41(4):704-709
The composition and structure of the radical-ion salt (ET)
2
[Hg(SCN)
2
Cl], a new organic metal withT
M-D=50 K, were established in an x-ray structure investigation. Principal crystallographic data:a=36.69(1),b=8.302(8),c=11.732(8) Å, =90.02(6)°, space groupCc, Z=4,d
calc=2.08 g/cm
3
,R=0.067. The crystal structure of the salt consists of an alternation of organic (cationic) and inorganic (anionic) layers along the axisa. The anionic layer consists of the polymeric chains in which the [Hg(SCN)
2
Cl]– ions are linked together along the axisc through secondary Hg···N bonds with lengths of 2.75(3) and 2.98(8) Å. On account of these interactions the trigonal configuration of the bonds of the Hg atom is built up to trigonal-bipyramidal. In the organic layer with a structure of the type the ET cations form dimers with an interplanar distance of 3.53 Å. ET cations belonging to neighboring dimers are linked together through shortened intermolecular S...S contacts with lengths of 3.40–3.50(2) Å.Institute of Chemical Physics, Russian Academy of Sciences, Chernogolovka 142432. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 4, pp. 903–909, April, 1992. 相似文献