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1.
The interaction of a highly dynamic poly(aryl acetylene) (poly‐ 1 ) with Li+, Na+, and Ag+ leads to macroscopically chiral supramolecular nanospheres, nanotubes, toroids, and gels. With Ag+, nanospheres with M helicity and tunable sizes are generated, which complement those obtained from the same polymer with divalent cations. With Li+ or Na+, poly‐ 1 yields chiral nanotubes, gels, or toroids with encapsulating properties and M helicity. Right‐handed supramolecular structures can be obtained by using the enantiomeric polymer. The interaction of poly‐ 1 with Na+ produces nanostructures whose helicity is highly dependent on the solvation state of the cation. Therefore, structures with either of the two helicities can be prepared from the same polymer by manipulation of the cosolvent. Such chiral nanotubes, toroids, and gels have previously not been obtained from helical polymer–metal complexes. Chiral nanospheres made of poly(aryl acetylene) that were previously assembled with metal(II) species can now be obtained with metal(I) species.  相似文献   

2.
The interaction of a highly dynamic poly(aryl acetylene) (poly‐ 1 ) with Li+, Na+, and Ag+ leads to macroscopically chiral supramolecular nanospheres, nanotubes, toroids, and gels. With Ag+, nanospheres with M helicity and tunable sizes are generated, which complement those obtained from the same polymer with divalent cations. With Li+ or Na+, poly‐ 1 yields chiral nanotubes, gels, or toroids with encapsulating properties and M helicity. Right‐handed supramolecular structures can be obtained by using the enantiomeric polymer. The interaction of poly‐ 1 with Na+ produces nanostructures whose helicity is highly dependent on the solvation state of the cation. Therefore, structures with either of the two helicities can be prepared from the same polymer by manipulation of the cosolvent. Such chiral nanotubes, toroids, and gels have previously not been obtained from helical polymer–metal complexes. Chiral nanospheres made of poly(aryl acetylene) that were previously assembled with metal(II) species can now be obtained with metal(I) species.  相似文献   

3.
Variable-aspect-ratio (length/diameter), one-dimensional (1-D) ZnO nanostructures (nanorods and nanowires) were prepared in alcohol/water solution by reacting a Zn2+ precursor with an organic weak base, tetramethylammonium hydroxide (Me4NOH). The effect of the experimental parameters (temperature, base concentration, reaction time, and water content) on nucleation, growth, and the final morphology of the ZnO nanostructures was investigated. The low-temperature syntheses (75-150 degrees C) yielded aspect ratios of the 1-D ZnO nanostructures that depended on the water content. The individual ZnO nanorods and nanowires were determined to be perfect, single crystals with their c axes as the primary growth direction.  相似文献   

4.
We present a novel method for the fabrication of one-dimensional (1-D) self-assembled monolayers and multilayers (SAMs) of (12-pyrrol-1-yl-dodecyl)-phosphonic acid (Py-DPA) on various polar surfaces using polyelectrolyte nanostructures as positive templates. Particularly, we demonstrate that (i) patterns of aligned 1-D polycation structures on a poly(dimethylsiloxane) stamp can be prepared by moving a droplet of polycation solution along the surface; (ii) these patterns can be used as templates for the ordered assembly of Py-DPA in water where Py-DPA carries a charge opposite to the charge of the template; and (iii) Py-DPA SAMs can then be transferred onto mica or silicon wafers by a printing process. These nanostructures with a polymerizable pyrrole headgroup might be useful for the creation of electrically conductive patterns of conjugated polymers.  相似文献   

5.
The one-dimensional (1-D) self-assembly property of an n-type hexaazatrinaphthylene (HATNA) discotic pi-conjugated molecule was studied. Structurally robust unimolecular columnar stacks of HATNA with tunable length have been fabricated through a combination of supramolecular self-assembly and post-polymerization approach. Moreover, microcontact printing can be utilized to transfer the self-assembled nanostructures to the surface to create desired functional patterns.  相似文献   

6.
Making use of N-P-acetamidobenzenesulfonyl-glycine acid (abbreviated as abglyH2),two transitional metal complexes [Zn(abglyH)(phen)2]ClO4·H2O (1) and Co(abglyH)2(bipy)2(H2O)2 (2) (phen = 1,10-phenanthroline,bipy = 4,4'-bipyridine) have been synthesized under mild conditions and characterized by IR,elemental analysis and X-ray diffraction analysis. Complex 1 is a monomeric compound which is further assembled by intermolecular hydrogen bonds and π-π interaction into a 2-D supramolecular network. Complex 2 is also a monomeric compound and further connected by intermolecular hydrogen bonds to form a 2-D supramolecular network. Fluorescent analysis shows that complex 1 has an emissive maximum at 364 nm in the solution state at room temperature.  相似文献   

7.
超分子自组装是发展超分子电子学的重要途径。随着纳米科学和技术的迅速发展,自组装技术已成功地应用于纳米尺度物质的维数、形貌和功能等的调控。作为构筑分子水平上一维、二维、三维有序功能结构和高有序分子聚集态结构的关键技术,超分子自组装技术有力地推动了具有优良光、电、磁性能的分子材料和纳米功能材料更深层次的研究。本文综述了超分子自组装在富勒烯科学领域的基础研究和应用,特别是对有利于自组织和自组装功能的富勒烯基衍生物的设计与合成、超分子作用力引导的具有特定结构的分子体系的可控自组装、以及富勒烯分子聚集态结构材料的光物理过程、超分子中电子转移和能量转移现象进行了描述;并对卟啉、四硫富瓦烯、碗烯和杯芳烃等一系列富π电子化合物和大环主体分子等包含[60]富勒烯的主体化合物的超分子作用和超分自组装体以及通过氢键、π-π作用、静电力和范德华力和金属配位作用形成的[60]富勒烯超分子自组装体进行了总结,对未来发展进行了展望。  相似文献   

8.
In this review,a group of two-dimensional(2D) hydrogen-bonded supramolecular networks developed in our laboratory are discussed.Our attention is mainly focused on:(1) recognition of Fe3+ through twocomponent molecular networks;(2) site-selective fabrication of 2D fullerene arrays;and(3) fabrication of the nanoporous structure regulated by photoisomerization reaction process.It is envisioned that special supramolecular nanostructures,through H-bonding interactions,can be constructed or reconstructed to be further investigated toward the research of multi-component systems,molecule recognition,single molecular switches,and host-guest supramolecular chemistry.  相似文献   

9.
Aqueous hybrid soft nanomaterials consisting of plural supramolecular architectures with a high degree of segregation (orthogonal coexistence) and precise hierarchy at the nano- and microscales, which are reminiscent of complex biomolecular systems, have attracted increasing attention. Remarkable progress has been witnessed in the construction of DNA nanostructures obtained by rational sequence design and supramolecular nanostructures of peptide derivatives through self-assembly under aqueous conditions. However, orthogonal self-assembly of DNA nanostructures and supramolecular nanostructures of peptide derivatives in a single medium has not yet been explored in detail. In this study, DNA microspheres, which can be obtained from three single-stranded DNAs, and three different supramolecular nanostructures (helical nanofibers, straight nanoribbons, and flowerlike microaggregates) of semi-artificial glycopeptides were simultaneously constructed in a single medium by a simple thermal annealing process, which gives rise to hybrid soft nanomaterials. Fluorescence imaging with selective staining of each supramolecular nanostructure uncovered the orthogonal coexistence of these structures with only marginal impact on their morphology. Additionally, the biostimuli-responsive degradation propensity of each supramolecular architecture is retained, and this may allow the construction of active soft nanomaterials exhibiting intelligent biofunctions.  相似文献   

10.
We present investigations on noncovalent bonding and supramolecular self-assembly of two related molecular building blocks at a noble metal surface: 4-[trans-2-(pyrid-4-yl-vinyl)]benzoic acid (PVBA) and 4-[(pyrid-4-yl-ethynyl)]benzoic acid (PEBA). These rigid, rodlike molecules comprising the same complementary moieties for hydrogen bond formation are comparable in shape and size. For PVBA, the ethenylene moiety accounts for two-dimensional (2-D) chirality upon confinement to a surface; PEBA is linear and thus 2-D achiral. Molecular films were deposited on a Ag(111) surface by organic molecular beam epitaxy and characterized by scanning tunneling microscopy. At low temperatures (around 150 K), both species form irregular networks of flat lying molecules linked via their endgroups in a diffusion-limited aggregation process. In the absence of kinetic limitations (adsorption or annealing at room temperature), hydrogen-bonded supramolecular assemblies form which are markedly different. With PVBA, enantiomorphic twin chains in two mirror-symmetric species running along a high-symmetry direction of the substrate lattice form by diastereoselective self-assembly of one enantiomer. The chirality signature is strictly correlated between neighboring twin chains. Enantiopure one-dimensional (1-D) supramolecular nanogratings with tunable periodicity evolve at intermediate coverages, reflecting chiral resolution in micrometer domains. In contrast, PEBA assembles in 2-D hydrogen-bonded islands, which are enantiomorphic because of the orientation of the supramolecular arrangements along low-symmetry directions of the substrate. Thus, for PVBA, chiral molecules form 1-D enantiomorphic supramolecular structures because of mesoscopic resolution of a 2-D chiral species, whereas with PEBA, the packing of an achiral species causes 2-D enantiomorphic arrangements. Model simulations of supramolecular ordering provide a deeper understanding of the stability of these systems.  相似文献   

11.
We report the supramolecular chemistry of several metal complexes of N-(4-pyridyl)benzamide (NPBA) with the general formula [Ma(NPBA)2AbSc], where M = Co2+, Ni2+, Zn2+, Mn2+, Cu2+, Ag+; A = NO3-, OAc-; S = MeOH, H2O; a = 0, 1, 2; b = 0, 1, 2, 4; and c = 0, 2. NPBA contains structural features that can engage in three modes of intermolecular interactions: (1) metal-ligand coordination, (2) hydrogen bonding, and (3) pi-pi stacking. NPBA forms one-dimensional (1-D) chains governed by hydrogen bonding, but when reacted with metal ions, it generates a wide variety of supramolecular scaffolds that control the arrangement of periodic nanostructures and form 1- (2-4), 2- (5), or 3-D (6-10) solid-state networks of hydrogen bonding and pi-pi stacking interactions in the crystal. Isostructural 7-9 exhibit a 2-D hydrogen bonding network that promotes topotaxial growth of single crystals of their isostructural family and generates crystal composites with two (11) and three (12) different components. Furthermore, 7-9 can also form crystalline solid solutions (M,M')(NPBA)2(NO3)2(MeOH)2 (M, M' = Co2+, Ni2+, or Zn2+, 13-16), where mixtures of Co2+, Ni2+, and Zn2+ share the same crystal lattice in different proportions to allow the formation of materials with modulated magnetic moments. Finally, we report the effects that multidimensional noncovalent networks exert on the magnetic moments between 2 and 300 K of 1-D (4), 2-D (5), and 3-D (7, 8, 10, and 13-16) paramagnetic networks.  相似文献   

12.
Six novel inorganic-organic coordination supramolecular networks based on a versatile linking unit 4-pyridylthioacetate (pyta) and inorganic Co(II), Cu(II), Ag(I), Zn(II), Mn(II) and Pb(II) salts have been prepared in water medium and structurally characterized by single-crystal X-ray diffraction analysis. Reaction of CoCl(2).6H(2)O with Hpyta afforded a neutral mononuclear complex [Co(pyta)(2)(H(2)O)(4)](1), which exhibits a two-dimensional (2-D) layered architecture through intermolecular O-HO interactions. Reaction of CuCl(2.2H(2)O with Hpyta yielded a neutral one-dimensional (1-D) coordination polymer [[Cu(pyta)(2)(H(2)O].0.5H(2)O](n)(2) consisting of rectangle molecular square units, which show a three-dimensional (3-D) supramolecular network through S...S and O-H...O weak interactions. However, when AgNO(3), Zn(OAc)(2).2H(2)O or MnCl(2).4H(2)O salts were used in the above self-assembled processes, the neutral 2-D coordination polymers [Ag(pyta)](n)(3), [[Zn(pyta)(2)].4H(2)O](n)(4) or [[Mn(pyta)(2)(H(2)O)]](n)(5) with different topologies were obtained, respectively. While substituting the transition metal ions used in 1-5 with Pb(OAc)(2).3H(2)O, a one-dimensional coordination polymer [Pb(pyta)(2)](n)(6), which shows a novel 2-fold interpenetrating 2-D supramolecular architecture through weak SS interactions, was isolated. It is interesting to note that the building block pyta anion exhibits different configurations and coordination modes in the solid structures of complexes 1-6. These results indicate that the versatile nature of this flexible ligand, together with the coordination preferences of the metal centers, play a critical role in construction of these novel coordination polymers or supramolecules. The spectral and thermal properties of these new materials have also been investigated.  相似文献   

13.
A novel Cu(Ⅱ) complex has been prepared by means of self-assembly of CuCl2,1-hexylimidazole L and oxalic acid(H2OX) in the presence of triethylamine,and structurally characterized by X-ray diffraction analysis.In complex 1,1-D polymer chains are formed through pentacoordinated Cu(Ⅱ),oxalate and bridging chlorine atoms.In the crystal packing of 1,the imidazole ring head-to-tail π-π stacking interactions exist between 1-D polymer chains and extend the 1-D polymer chains into 2-D supramolecular layers.The fluorescence emission spectra of L and 1 were described.  相似文献   

14.
Inspired by natural enzymes, hierarchical catalytic supramolecular nanostructures were developed by the co-assembly of hemin and glucose oxidase (or Au NPs) with the photosensitive ferrocene–tyrosine (Fc-Y) molecule. Illuminated by white light, the Fc-Y molecules are polymerized and co-assemble with hemin into truncated polyhedrons. The Au NPs grew in situ at the surface of the co-assembled polyhedrons, achieving ordered supramolecular nanostructures. Because the Au NPs can serve as an artificial glucose oxidase and the hemin could act as a peroxidase mimic, the supramolecular hybrid nanostructures were used to mimic natural enzymes and catalyze the glucose conversion cascade reaction. The hybrid Au NPs@Fc-Y&hemin polyhedrons showed superior catalytic activity, good reusability, and maintained the catalytic activity over a wide temperature and pH range. The study demonstrates a feasible strategy to construct hierarchical co-assembled supramolecular nanostructures as multi-enzyme mimics, with potential applications in biocatalysis and biosensing.  相似文献   

15.
Wang L  Yang M  Li G  Shi Z  Feng S 《Inorganic chemistry》2006,45(6):2474-2478
Employing an unsymmetrical 1,2,4-benzenetricarboxylate as a bridging ligand, a new 3-D chiral cadmium coordination polymer [Cd(2)(OH)(1,2,4-BTC)] (1,2,4-BTC = 1,2,4-benzenetricarboxylate) has been prepared under hydrothermal conditions and characterized by single crystal X-ray diffraction. This compound crystallizes in the orthorhombic space group P2(1)2(1)2(1), with cell parameters a = 6.900(2) A, b = 7.404(3) A, c = 19.116(5) A, V = 976.5(5) A(3), and Z = 4. Its structure contains 2-D Cd-O-Cd connectivity, which is further linked by the 1,2,4-BTC ligand into a 3-D supramolecular framework. The 1,2,4-BTC ligand shows a novel and unprecedented coordination mode: nine bonds to eight metals with each carboxylate as a tridentate group. The compound exhibits intense photoluminescence at room temperature and shows distinct NLO properties. On the basis of the results of TG/DTA analyses, the structure is thermally stable up to approximately 380 degrees C.  相似文献   

16.
Du M  Jiang XJ  Zhao XJ 《Inorganic chemistry》2007,46(10):3984-3995
A series of nine mixed-ligand metal-organic frameworks (MOFs) have been prepared by the combination of a bent dipyridyl linker 4-amino-3,5-bis(4-pyridyl)-1,2,4-triazole (bpt) and three benzenedicarboxylate isomers (pa = phthalate, ip = isophthalate, and tp = terephthalate), respectively, with different metal ions such as CoII, NiII, CuII, ZnII, and CdII. The framework structures of these neutral polymeric complexes have been determined by the X-ray single-crystal diffraction technique. Structural analysis reveals that the benzenedicarboxylate isomers display versatile coordination modes to manage the metal ions to form 1-D chain or ribbon arrays, which are further extended via the exo-bidentate bpt connectors to give rise to a variety of coordination networks, such as a simple (4,4) layer, 2-D double layer with decorated (4,4) topology, 2-D layer with decorated (3,6) topology, 2-D bilayer with 82.10 topology (2-fold interpenetration), 3-D polythreaded architecture (1-D + 2-D), and 2-fold interpenetrating porous lattice of (4,4) layers. The accessorial secondary interactions such as hydrogen bonding and/or aromatic stacking are also helpful for the extension and stabilization of the final supramolecular aggregates. This work evidently indicates that the isomeric effect of the anionic benzenedicarboxylate is significant in the construction of these network structures, which are also well regulated by the metal centers. The ZnII and CdII MOFs exhibit strong solid-state luminescence emissions at room temperature, which originate differently from intraligand transition or ligand-to-metal charge transfer. Thermal stability of these crystalline materials has been explored by thermogravimetric analysis of mass loss. The 3-D host frameworks of MOFs 8 and 9 show similar porous cavities, and their desorption/adsorption behaviors of guest solvents have also been investigated.  相似文献   

17.
This review presents a summary of the recent research progresses on fullerene self-assembly and supramolecular nanostructures. Fullerene nanospheres, one-dimensional nanowires/nanotubes, and two-dimensional layers were studied with various microscopic techniques such as the scanning tunneling microscopy, scanning electronic microscopy, and the transmission electron microscopy etc. It was revealed that the fullerene self-assembling structures were determined by both the fullerene intermolecular interactions and the fullerene–substrate interaction, therefore, different fullerene supramolecular nanostructures and morphologies could be obtained through controlling experimental conditions, e.g., the chemical modification of fullerenes by different chemical groups, the treatment of substrates, or the adopting of solvents etc.  相似文献   

18.
The diffusion reaction of TBA2Cu(II)Cl4 (TBA = tetrabutylammonium) and a N-containing organic donor, BP-TTF [=bis(pyrazino)tetrathiafulvalene], yielded a 3-D supramolecular Cu complex, [CuCl2(BP-TTF)] (1). The magnetic measurement of 1 exhibits an antiferromagnetic interaction by fitting a Bonner-Fisher model from 2 to 300 K with S = 1/2 and J = -3.5 K between Cu(IotaIota) mediated by self-assembling donor columns.  相似文献   

19.
Wang X  Guo Y  Li Y  Wang E  Hu C  Hu N 《Inorganic chemistry》2003,42(13):4135-4140
The spherical Lindquist type polyoxometalate, Mo(6)O(19)(2)(-), has been used as a noncoordinating anionic template for the construction of novel three-dimensional lanthanide-aromatic monocarboxylate dimer supramolecular networks [Ln(2)(DNBA)(4)(DMF)(8)][Mo(6)O(19)] (Ln = La 1, Ce 2, and Eu 3, DNBA = 3,5-dinitrobenzoate, DMF = dimethylformamide). The title compounds are characterized by elemental analyses, IR, and single-crystal X-ray diffractions. X-ray diffraction experiments reveal that two Ln(III) ions are bridged by four 3,5-dinitrobenzoate anions as asymmetrically bridging ligands, leading to dimeric cores, [Ln(2)(DNBA)(4)(DMF)(8)](2+); [Ln(2)(DNBA)(4)(DMF)(8)](2+) groups are joined together by pi-pi stacking interactions between the aromatic groups to form a two-dimensional grid-like network; the 2-D supramolecular layers are further extended into 3-D supramolecular networks with 1-D box-like channels by hydrogen-bonding interactions, in which hexamolybdate polyanions reside. The compounds represent the first examples of 3-D carboxylate-bridged lanthanide dimer supramolecular "host" networks formed by pi-pi stacking and hydrogen-bonding interactions encapsulating noncoordinating "guest" polyoxoanion species. The fluorescent activity of compound 3 is reported.  相似文献   

20.
Novel cage-like and electromagnetic functional polyaniline (PANI)/CoFe2O4 composite nanostructures, in which the self-assembled PANI nanofibers (approximately 15 nm in diameter) entwined around the octahedral CoFe2O4 magnet acting as the nucleation site or template, were successfully prepared by FeCl3 as either oxidant and dopant via a self-assembly process. The coordination effect of the magnet as a nucleation site or template and the magnetic interaction between the PANI nanofibers and CoFe2O4 as a driving force results in such cage-like nanostructures. The cage-like composite nanostructures not only have high conductivity (sigmamax approximately 5.2 S/cm), but also show a typical ferromagnetic behavior.  相似文献   

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