Synthesis and electronic properties of alkyne-TTFAQ based molecular wires

We herein describe the first synthesis of a series of π-extend tetrathiafulvalene and alkyne based conjugated molecular wires. Electronic properties of these compounds were characterized by cyclic voltammetry, UV-vis absorption, and fluorescence spectroscopy.     

Synthesis of a π-extended TTF-perylenediimide donor-acceptor dyad

A donor-acceptor dyad containing perylenediimide as the electron acceptor and π-extended tetrathiafulvalene as electron donor has been successfully synthesized by means of a Wittig reaction. Cyclic voltammetry and absorption spectroscopy show that both electroactive units preserve their nature, whereas preliminar photophysical investigations show a strong fluorescence quenching.     

Building up 1‐D, 2‐D,and 3‐D Polyiodide Frameworks by Finely Tuning the Size of Aryls on Ar‐S‐TTF in the Charge‐Transfer (CT) Complexes of Ar‐S‐TTFs and Iodine

The arylthio‐substituted tetrathiafulvalenes (Ar‐S‐TTFs) are electron donors having three reversible states, neutral, cation radical, and dication. The charge‐transfer (CT) between Ar‐S‐TTFs ( TTF1 — TTF3 ) and iodine (I₂) is reported herein. TTF1 — TTF3 show the CT with I₂ in the CH₂Cl₂ solution, but they are not completely converted into cation radical state. In CT complexes of TTF1 — TTF3 with I₂, the charged states of Ar‐S‐TTFs are distinct from those in solution. TTF1 is at cation radical state, and TTF2 — TTF3 are oxidized to dication. The iodine components in complexes show various structures including 1‐D chain of V‐shaped (I₅)^–, and 2‐D and 3‐D iodine networks composed of I₂ and (I₃)^–.     

TTF·M（dmit）2型电荷转移配合物的合成及其拉曼光谱

合成了８种四硫富瓦烯·二－（１，３－二硫杂环戊－４－烯－２－硫酮－４，５－二巯基）金属（缩写为ＴＴＦ·Ｍ（ｄｍｉｔ）－２）电荷转移配合物，其中７种配合物为首次合成，拉曼光谱的研究结果表明，对同一种电子受体，电子给体的还原电势Ｅｐ越小，配合物的电荷转移度ρ值越大。     

四硫富瓦烯为电子媒介体的葡萄糖生物传感器的研究

本采用四硫富瓦烯（ＴＴＦ）作为葡萄糖氧化酶与玻碳电极之间的电子媒介体，把葡萄糖氧化酶因定在Ｎａｆｉｏｎ－ＴＴＦ修饰电极上，制成葡萄糖生物传感器。用这种传感器测定人体血清中葡萄糖的含量，其线性范围在４．０×１０＾－５～１０＾－３ｍｏｌ／Ｌ之间，响应时间为２０ｓ。该传感器具有选择性、重现性好，灵敏度高等优点。     

Single‐Walled Carbon Nanotube Based Molecular Switch Tunnel Junctions

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.     

Synthesis and crystal structure of the deuterated organic conductor, (d8-ET)4[Hg2(SCN)4Cl2]

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).     

四硫富瓦烯衍生物的银(Ⅰ)配位聚合物的合成与表征

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.     

Topological effects of a rigid chiral spacer on the electronic interactions in donor-acceptor ensembles

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.