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101.
合成了双羟甲基及双甲氧甲酰基取代的双(二硫代亚乙基)四硫代富瓦烯,给出了它们的质谱、核磁共振氢谱和碳谱,并讨论了影响反应的一些因素。 相似文献
102.
103.
“桥式”双四硫富瓦烯衍生物的合成及电化学行为 总被引:4,自引:0,他引:4
循环伏安法;紫外-可见光谱法;“桥式”双四硫富瓦烯衍生物的合成及电化学行为 相似文献
104.
Javier Castells-Gil Samuel Mañas-Valero Dr. Iñigo J. Vitórica-Yrezábal Dr. Duarte Ananias Prof. João Rocha Raul Santiago Prof. Stefan T. Bromley Dr. José J. Baldoví Prof. Eugenio Coronado Dr. Manuel Souto Dr. Guillermo Mínguez Espallargas 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(54):12636-12643
Tetrathiafulvalene-lanthanide (TTF-Ln) metal–organic frameworks (MOFs) are an interesting class of multifunctional materials in which porosity can be combined with electronic properties such as electrical conductivity, redox activity, luminescence and magnetism. Herein a new family of isostructural TTF-Ln MOFs is reported, denoted as MUV-5(Ln) (Ln=Gd, Tb, Dy, Ho, Er), exhibiting semiconducting properties as a consequence of the short intermolecular S⋅⋅⋅S contacts established along the chain direction between partially oxidised TTF moieties. In addition, this family shows photoluminescence properties and single-molecule magnetic behaviour, finding near-infrared (NIR) photoluminescence in the Yb/Er derivative and slow relaxation of the magnetisation in the Dy and Er derivatives. As such properties are dependent on the electronic structure of the lanthanide ion, the immense structural, electronic and functional versatility of this class of materials is emphasised. 相似文献
105.
Dr. Atanu Jana Dr. Masatoshi Ishida Prof. Hiroyuki Furuta 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(13):4466-4472
Two sterically crowded benzo-tetrathiafulvalene (BTTF)-annulated expanded porphyrins ( BTTF7-F and BTTF8 ) are synthesized. Detailed photophysical investigations reveal their intrinsic intramolecular charge transfer (CT) character, originated from partial electron transfer from electron-rich TTF units to the relatively electron-deficient macrocyclic core. This finding stands in contrast to what was observed in the previously reported Figure-of-eight conformer of BTTF-annulated [28]hexaphyrin ( BTTF6 ), in which a typical π–π* electronic transition from HOMO to LUMO was observed. However, core expansion in BTTF7-F and BTTF8 makes the oligopyrrole macrocyclic cores relatively more electron-deficient, facilitating the effective intramolecular CT process. Comparative electrochemical investigations reveal that the current generated at the oxidative region is directly proportional to the number of TTF units attached to the macrocyclic core. This work demonstrates the control of the intramolecular CT process through incremental addition of TTF units to the macrocyclic core. Facile multielectron electrochemical oxidations of these expanded porphyrins suggest that they behave like potential multielectron reservoirs. 相似文献
106.
以4,5-二(2'-氰乙基硫基)-1,3-二硫杂环戊烯-2-硫酮为原料经甲醇钠消除一个氰乙基生成4-(2'-氰乙基硫基)-1,3-二硫杂环戊烯-2-硫酮的单钠盐, 生成的单钠盐再与1,4-二(氯甲基)苯反应生成4,4'-二(2-氰乙基硫基)-5,5'-(1,4-二亚甲基苯)-二(1,3-二硫杂环戊烯-2-硫酮). 接着在乙酸汞的作用下生成4,4'-二(2-氰乙基硫基)-5,5'-(1,4-二亚甲基苯)-二(1,3-二硫杂环戊烯-2-酮), 此化合物在亚磷酸三乙酯的作用下发生偶联反应, 生成由TTF单元和苯单元构建的新型四硫富瓦烯环蕃和另一种四硫富瓦烯衍生物. 并分别通过循环伏安法和化学氧化法对它们及其导电复合物的电化学性质和紫外光谱进行了研究. 还研究了这种新型四硫富瓦烯环蕃在金纳米颗粒表面自组装行为. 相似文献
107.
Quantum Mechanical and Experimental Validation that Cyclobis(paraquat‐p‐phenylene) Forms a 1:1 Inclusion Complex with Tetrathiafulvalene 下载免费PDF全文
Dr. Karel J. Hartlieb Dr. Wei‐Guang Liu Dr. Albert C. Fahrenbach Anthea K. Blackburn Dr. Marco Frasconi Dr. Nema Hafezi Dr. Sanjeev K. Dey Dr. Amy A. Sarjeant Charlotte L. Stern Prof. William A. Goddard III Prof. J. Fraser Stoddart 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(8):2736-2745
The promiscuous encapsulation of π‐electron‐rich guests by the π‐electron‐deficient host, cyclobis(paraquat‐p‐phenylene) (CBPQT4+), involves the formation of 1:1 inclusion complexes. One of the most intensely investigated charge‐transfer (CT) bands, assumed to result from inclusion of a guest molecule inside the cavity of CBPQT4+, is an emerald‐green band associated with the complexation of tetrathiafulvalene (TTF) and its derivatives. This interpretation was called into question recently in this journal based on theoretical gas‐phase calculations that reinterpreted this CT band in terms of an intermolecular side‐on interaction of TTF with one of the bipyridinium (BIPY2+) units of CBPQT4+, rather than the encapsulation of TTF inside the cavity of CBPQT4+. We carried out DFT calculations, including solvation, that reveal conclusively that the CT band emerging upon mixing TTF with CBPQT4+ arises from the formation of a 1:1 inclusion complex. In support of this conclusion, we have performed additional experiments on a [2]rotaxane in which a TTF unit, located in the middle of its short dumbbell, is prevented sterically from interacting with either one of the two BIPY2+ units of a CBPQT4+ ring residing on a separate [2]rotaxane in a side‐on fashion. This [2]rotaxane has similar UV/Vis and 1H NMR spectroscopic properties with those of 1:1 inclusion complexes of TTF and its derivatives with CBPQT4+. The [2]rotaxane exists as an equimolar mixture of cis‐ and trans‐isomers associated with the disubstituted TTF unit in its dumbbell component. Solid‐state structures were obtained for both isomers, validating the conclusion that the TTF unit, which gives rise to the CT band, resides inside CBPQT4+. 相似文献
108.
YANG XingYuan ZHANG DeQing ZHANG GuanXin & ZHU DaoBen Beijing National Laboratory for Molecular Sciences Organic Solids Laboratory 《中国科学B辑(英文版)》2011,(4)
Tetrathiafulvalene (TTF) and its derivatives have been intensively investigated for conducting materials for more than 30 years.As π-electron donors,TTF and its derivatives can be reversibly transformed into the respective TTF.+ and TTF2+.Due to its reversible feature,the TTF unit has been widely employed as the building block for switchable systems.In recent years studies of conducting nanostructures of TTF derivatives have received more and more attention.One simple way to prepare nano-structures is throu... 相似文献
109.
为了发展转变点温度(Tc)高的有机磁性分子,设计合成了4,5-四硫富瓦烯-双(2,3,6,7-二苯基-氮杂环庚烷-1-氧化物)。反应混合物均经硅胶柱和设备HPLC分离和纯化,产物的结构由MS、^1^HNMR、^1^3CNMR等确定。 相似文献
110.
Chun-Guang Liu 《Molecular physics》2014,112(2):199-205
A molecular switch having large contrast on the second-order nonlinear optical (NLO) properties has been studied based on tetrathiafulvalene (TTF)-π-polynitrofluorene (PTF) molecule. It can afford to switch second-order NLO response across 10 stable states by an effective combination of its photoisomerisation and redox properties. According to density functional theory (DFT) finite field calculations (BHandHLYP/CAM-B3LYP/LC-BLYP/6-31g(d)), the redox-active TTF, TCNQ (7,7′,8,8′-tetracyano-p-quinodimethane) units, and a photoisomerised chromophore (thiophene derivative of perfluorocyclopentene) act as the tuning centre to switch second-order NLO responses. Meanwhile, time-dependent DFT method has been employed to calculate excited-state nature for getting more insights of the second-order NLO responses. 相似文献