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71.
Self‐Assembled Architectures with Segregated Donor and Acceptor Units of a Dyad Based on a Monopyrrolo‐Annulated TTF–PTM Radical 下载免费PDF全文
Manuel Souto Dr. Marta V. Solano Morten Jensen Dan Bendixen Francesca Delchiaro Prof. Alberto Girlando Prof. Anna Painelli Prof. Jan O. Jeppesen Prof. Concepció Rovira Dr. Imma Ratera Prof. Jaume Veciana 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(24):8816-8825
An electron donor–acceptor dyad based on a polychlorotriphenylmethyl (PTM) radical subunit linked to a tetrathiafulvalene (TTF) unit through a π‐conjugated N‐phenyl–pyrrole–vinylene bridge has been synthesized and characterized. The intramolecular electron transfer process and magnetic properties of the radical dyad have been evaluated by cyclic voltammetry, UV/Vis spectroscopy, vibrational spectroscopy, and ESR spectroscopy in solution and in the solid state. The self‐assembling abilities of the radical dyad and of its protonated non‐radical analogue have been investigated by X‐ray crystallographic analysis, which revealed that the radical dyad produced a supramolecular architecture with segregated donor and acceptor units in which the TTF subunits were arranged in 1D herringbone‐type stacks. Analysis of the X‐ray data at different temperatures suggests that the two inequivalent molecules that form the asymmetric unit of the crystal of the radical dyad evolve into an opposite degree of electronic delocalization as the temperature decreases. 相似文献
72.
R. Alan Aitken Stephen J. Costello Neil J. Wilson 《Phosphorus, sulfur, and silicon and the related elements》2013,188(5-6):1363-1367
Abstract A new donor–acceptor diad compound 6 with the donor dihydro-TTF and acceptor quinone functions in very close proximity has been prepared and characterized. The X-ray structure shows an interesting stacking pattern and electrochemically it undergoes two reversible oxidations and two reversible reductions. An ESR signal has been observed due to thermal population of the radical anion/radical cation state. 相似文献
73.
Dimeric Tetrathiafulvalene Linked to pseudo‐ortho‐[2.2]Paracyclophane: Chiral Electrochromic Properties and Use as a Chiral Dopant 下载免费PDF全文
Kosuke Kobayakawa Dr. Masashi Hasegawa Hiroaki Sasaki Junta Endo Dr. Hideyo Matsuzawa Dr. Katsuya Sako Dr. Jun Yoshida Dr. Yasuhiro Mazaki 《化学:亚洲杂志》2014,9(10):2751-2754
A dimeric tetrathiafulvalene installed into a chiral pseudo‐ortho‐[2.2]paracyclophane framework was synthesized as a novel chiral electrochromic material. This compound exhibited pronounced chiroptical properties in the UV‐Vis‐NIR range depending on its redox states without racemization. Each enantiomer was examined as a chiral dopant for nematic liquid crystals (LCs), and the induced helicity of the LC solvent was in accord with that of the tetrathiafulvalene compound. 相似文献
74.
Huimin Ding Yonghai Li Hui Hu Dr. Yimeng Sun Jianguo Wang Caixing Wang Prof. Dr. Cheng Wang Dr. Guanxin Zhang Prof. Dr. Baoshan Wang Prof. Dr. Wei Xu Prof. Dr. Deqing Zhang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(45):14614-14618
Two‐dimensional covalent organic frameworks (2D COFs) provide a unique platform for the molecular design of electronic and optoelectronic materials. Here, the synthesis and characterization of an electroactive COF containing the well‐known tetrathiafulvalene (TTF) unit is reported. The TTF‐COF crystallizes into 2D sheets with an eclipsed AA stacking motif, and shows high thermal stability and permanent porosity. The presence of TTF units endows the TTF‐COF with electron‐donating ability, which is characterized by cyclic voltammetry. In addition, the open frameworks of TTF‐COF are amenable to doping with electron acceptors (e.g., iodine), and the conductivity of TTF‐COF bulk samples can be improved by doping. Our results open up a reliable route for the preparation of well‐ordered conjugated TTF polymers, which hold great potential for applications in fields from molecular electronics to energy storage. 相似文献
75.
采用缓慢挥发溶剂的方法合成了硫原子桥联芳基取代四硫富瓦烯(Ar-S-TTF)与碘的3种电荷转移复合物(1+·)(I3)·I2、(2+·)(I5)·I2和(32+)(I3)2,采用单晶X射线衍射、紫外可见光谱、循环伏安对其进行了表征。复合物(1+·)(I3)·I2为C2/c空间群,1+·呈椅式构型。化合物1与碘之间在溶液中和复合物中电荷转移一致。复合物(2+·)(I5)·I2为P1空间群,2+·呈椅式构型。复合物(32+)(I3)2为Pbca空间群,32+呈独特的平面构型。化合物2和3与碘之间在溶液中和复合物中呈现不同的电荷转移。复合物中聚碘阴离子呈现不同的堆积结构:由I3-或I5-/I2组成的一维链状和I3-/I2组成的二维网格状。 相似文献
76.
77.
78.
Cover Picture: Design and Sensing Properties of a Self‐Assembled Supramolecular Oligomer (Chem. Eur. J. 6/2016) 下载免费PDF全文
79.
Hierarchical Self‐Assembly of Supramolecular Helical Fibres from Amphiphilic C3‐Symmetrical Functional Tris(tetrathiafulvalenes) 下载免费PDF全文
Dr. Flavia Pop Caroline Melan Dr. Ion Danila Dr. Mathieu Linares Dr. David Beljonne Prof. David B. Amabilino Dr. Narcis Avarvari 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(52):17443-17453
The preparation and self‐assembly of the enantiomers of a series of C3‐symmetric compounds incorporating three tetrathiafulvalene (TTF) residues is reported. The chiral citronellyl and dihydrocitronellyl alkyl chains lead to helical one dimensional stacks in solution. Molecular mechanics and dynamics simulations combined with experimental and theoretical circular dichroism support the observed helicity in solution. These stacks self‐assemble to give fibres that have morphologies that depend on the nature of the chiral alkyl group and the medium in which the compounds aggregate. An inversion of macroscopic helical morphology of the citronellyl compound is observed when compared to analogous 2‐methylbutyl chains, which is presumably a result of the stereogenic centre being further away from the core of the molecule. This composition still allows both morphologies to be observed, whereas an achiral compound shows no helicity. The morphology of the fibres also depends on the flexibility at the chain ends of the amphiphilic components, as there is not such an apparently persistent helical morphology for the dihydrocitronellyl derivative as for that prepared from citronellyl chains. 相似文献
80.
Dr. Hong‐Peng Jia Dr. Jie Ding Dr. Ying‐Fen Ran Dr. Shi‐Xia Liu Dr. Carmen Blum Dr. Irina Petkova Prof. Andreas Hauser Prof. Silvio Decurtins 《化学:亚洲杂志》2011,6(12):3312-3321
An efficient synthetic approach to a symmetrically functionalized tetrathiafulvalene (TTF) derivative with two diamine moieties, 2‐[5,6‐diamino‐4,7‐bis(4‐pentylphenoxy)‐1,3‐benzodithiol‐2‐ylidene]‐4,7‐bis(4‐pentylphenoxy)‐1,3‐benzodithiole‐5,6‐diamine ( 2 ), is reported. The subsequent Schiff‐base reactions of 2 afford large π‐conjugated multiple donor–acceptor (D–A) arrays, for example, the triad 2‐[4,9‐bis(4‐pentylphenoxy)‐1,3‐dithiolo[4,5‐g]quinoxalin‐2‐ylidene]‐4,9‐bis(4‐pentylphenoxy)‐1,3‐dithiolo[4,5‐g]quinoxaline ( 8 ) and the corresponding tetrabenz[bc,ef,hi,uv]ovalene‐fused pentad 1 , in good yields and high purity. The novel redox‐active nanographene 1 is so far the largest known TTF‐functionalized polycyclic aromatic hydrocarbon (PAH) with a well‐resolved 1H NMR spectrum. The electrochemically highly amphoteric pentad 1 and triad 8 exhibit various electronically excited charge‐transfer states in different oxidation states, thus leading to intense optical intramolecular charge‐transfer (ICT) absorbances over a wide spectral range. The chemical and electrochemical oxidations of 1 result in an unprecedented TTF?+ radical cation dimerization, thereby leading to the formation of [ 1 ?+]2 at room temperature in solution due to the stabilizing effect, which arises from strong π–π interactions. Moreover, ICT fluorescence is observed with large solvent‐dependent Stokes shifts and quantum efficiencies of 0.05 for 1 and 0.035 for 8 in dichloromethane. 相似文献