Article

1998 ◽  
Vol 76 (11) ◽  
pp. 1654-1659
Author(s):  
F Bensebaa ◽  
T H Ellis ◽  
E Kruus ◽  
R Voicu ◽  
Y Zhou
Keyword(s):  
Self Assembly ◽  
Metal Ion ◽  
Layered Materials ◽  
The Self ◽  
X Ray Diffraction ◽  
X Ray ◽  
Alkyl Chains ◽  
Metal Atoms ◽  
Hexagonal Arrangement ◽  
Key Features

Layered materials composed of metal-alkanethiolate units have been synthesized and characterized. The self-assembly occurs at the interface between a metal-ion-containing aqueous phase and an alkanethiol-containing organic phase. Key features of the structure have been determined from X-ray diffraction and infrared spectroscopy measurements. The highly ordered bilayers are characterized by tilted, all-trans alkyl chains. A new model for the in-plane structure has been presented, which is based on a hexagonal arrangement of metal atoms in the central plane.Key words: self-assembly, alkanethiolates, layered materials, vibrational spectroscopy.

The Evaluation of TiTe2 as a Diffusion Barrier in the Formation of Low Thermal Conductivity Nanolaminates with Bi2Te3 and Sb2Te3

2010 ◽  
Vol 74 ◽  
pp. 38-47
Author(s):  
Clay Mortensen ◽  
Paul Zschack ◽  
David C. Johnson
Keyword(s):  
Thermal Conductivity ◽  
Diffusion Barrier ◽  
Self Assembly ◽  
Low Temperatures ◽  
Annealing Temperature ◽  
The Self ◽  
High Angle ◽  
X Ray Diffraction ◽  
Amorphous Precursor ◽  
X Ray

The evolution of designed [(Ti-Te)]x[(Sb-Te)]y, [(Bi-Te)]x[(Sb-Te)]y, [(Ti-Te)]w[(Bi-Te)]x[(Sb-Te)]y and [(Ti-Te)]w[(Bi-Te)]x[(Ti-Te)]y[(Sb-Te)]z precursors were followed as a function of annealing temperature and time using both low and high angle x-ray diffraction techniques to probe the self assembly into nanolaminate materials. The [(Bi-Te)]x[(Sb-Te)]y precursors were found to interdiffuse at low temperatures to form a (BixSb1-x)2Te3 alloy. The [(Ti-Te)]x[(Bi-Te)]y and [(Ti-Te)]x[(Sb-Te)]y precursors formed ordered nanolaminates [{(TiTe2)}1.35]x[Bi2Te3]y and [{(TiTe2)}1.35]x[Sb2Te3]y respectively. The [(Ti-Te)]w[(Bi-Te)]x[(Sb-Te)]x precursors formed [{(TiTe2)}1.35]w[(Bi0.5Sb0.5)2Te3]2x nanolaminates on annealing, as the bismuth and antimony layers interdiffused. Over the range of TiTe2 thicknesses used in [(Ti-Te)]w[(Bi-Te)]x[(Ti-Te)]y[(Sb-Te)]z precursors, Bi and Sb were found to interdiffuse through the 2-4 nm thick Ti-Te layers, resulting in the formation of (BixSb1-x)2Te3 alloy layers as part of the final nanolaminated products. When the Bi-Te and Sb-Te thicknesses were equal in the amorphous precursors, symmetric [{(TiTe2)}1.35]m[(Bi0.5Sb0.5)2Te3]n nanolamiantes were formed. When the thicknesses of Bi-Te and Sb-Te layers were not equal in the amorphous precursor, asymmetric [(TiTe2)1.35]m[(BixSb1-x)2Te3]n[(TiTe2)1.35]m[(BixSb1-x)2Te3]p nanolaminates were formed. These results imply that to form (A)w(B)x(C)y nanolaminates using designed layered precursors all three components must be immiscible. To form (A)x(B)y(A)x(C)z nanolaminates, the components must be immiscible or the precursor to the A component and the A component itself must be an effective interdiffusion barrier preventing B and C from mixing.

Hydrothermal Syntheses, Crystal Structures, and Luminescent Properties of Two MnII Coordination Polymers: From Two-Fold Interpenetrated pcu Topological Net to Polycatenated 2D+2D→3D Framework

2015 ◽  
Vol 68 (2) ◽  
pp. 322 ◽  
Author(s):  
Wenlong Liu ◽  
Mengqiang Wu ◽  
Xueying Wang ◽  
Wei Wang ◽  
Dayu Liu ◽  
...  
Keyword(s):  
Dicarboxylic Acid ◽  
Coordination Polymers ◽  
Self Assembly ◽  
Room Temperature ◽  
Luminescent Properties ◽  
The Self ◽  
X Ray Diffraction ◽  
X Ray ◽  
3D Framework ◽  
Dimethyl Benzene

Using a hydrothermal synthesis, the self-assembly of MnII ions and 1,4-bis(1-imidazol-yl)-2,5-dimethyl benzene with two dicarboxylate ligands, 2-nitrobenzene-1,4-dicarboxylic acid (2-H2ata) and 5-methylbenzene-1,3-dicarboxylic acid (5-CH3-H2ip) constructed two interesting coordination polymers: [Mn(2-ata)(bimb)]n (1) and {[Mn(5-CH3-ip)(bimb)1.5]·2H2O}n (2), where bimb refers to 1,4-bis(1-imidazol-yl)-2,5-dimethyl benzene. Their structures were determined by single-crystal X-ray diffraction, elemental analysis, and infrared spectroscopy. Complex 1 exhibits a 2-fold interpenetrated pcu net. Complex 2 shows an unusual polycatenated 2D+2D→3D framework. In addition, the solid-state photoluminescent properties of 1 and 2 were investigated at room temperature.

Synthese und Koordinationschemie eines neuartigen Bistetrazols: Ein 1D-Metallopolymer durch Selbstorganisation koordinativ ungesättigter Zink(II)-M4onomere [1] / Synthesis and Coordination Chemistry of a New Bistetrazole: A 1D-Metallopolymer via Self-Assembly of Monomeric Zinc(II)-Buildingblocks

1995 ◽  
Vol 50 (4) ◽  
pp. 642-648 ◽  
Author(s):  
Rolf W. Saalfrank ◽  
Klaus Schobert ◽  
Stefan Trümmer ◽  
Alexander Wolski
Keyword(s):  
Coordination Chemistry ◽  
Self Assembly ◽  
Intermediate Formation ◽  
The Self ◽  
Polymeric Chain ◽  
X Ray Diffraction ◽  
Bridging Ligands ◽  
Subsequent Formation ◽  
X Ray ◽  
Polymeric Compounds

The new bistetrazole 13 has been obtained by subsequent formation of the two heterocyclic units. In methanolic solution 13 reacts with zinc(II) acetate to yield the pseudo-meso-1 D-coordination polymer [ZnL2(MeOH)]n (n = ∞) 14. The structure of 14 was established by single crystal X-ray diffraction. The generation of the polymeric chain 14 is understandable, if intermediate formation of coordinatively unsaturated zinc(II) buildingblocks (Δ)-15 and (Λ)-15 is assumed. Alternating linkage of the self-complementary chiral monomers 15, across one cyanofunction each, leads to 14 with zinc being essentially octahedrally coordinated. Compared with polymeric compounds of similar bridging ligands, the Zn ··· N≡C-distance in 14 (225,7 pm) is short.

Fabrication and Hydrogen Sensing Property of In2O3 Nanotowers

2013 ◽  
Vol 834-836 ◽  
pp. 913-916
Author(s):  
Zhao Qiang Zheng ◽  
Huan Yu Wu ◽  
Bing Wang
Keyword(s):  
Self Assembly ◽  
Thermal Evaporation ◽  
Sensor Response ◽  
The Self ◽  
X Ray Diffraction ◽  
Excellent Performance ◽  
X Ray ◽  
Hydrogen Sensing ◽  
Morphology And Structure ◽  
Prepared Nanorods

In2O3nanotowers have been fabricated on Au item-shaped parallel electrodes using thermal evaporation of the mixed powders of In2O3and graphite with Au catalysts. The morphology and structure of the prepared nanorods are determined on the basis of field-emission scanning electron microscopy (FESEM) and x-ray diffraction (XRD). The self-assembly grown sensors of In2O3nanotowers have excellent performance in sensor response to hydrogen concentration of 1000 ppm under operated temperature of 300°C.

Two new isostructural mercury(II) complexes involving the N-heterocyclic 1-[(benzotriazol-1-yl)methyl]-1H-1,3-imidazole ligand: syntheses, structures and properties

2017 ◽  
Vol 73 (4) ◽  
pp. 314-318 ◽  
Author(s):  
Xu Wei ◽  
Jian-Hua Li ◽  
Qiu-Ying Huang ◽  
Xiang-Ru Meng
Keyword(s):  
Solid State ◽  
Hydrogen Bonds ◽  
Ir Spectra ◽  
Self Assembly ◽  
Three Dimensional ◽  
The Self ◽  
X Ray Diffraction ◽  
X Ray ◽  
Heterocyclic Ligand ◽  
Structures And Properties

The unsymmetrical N-heterocyclic ligand 1-[(benzotriazol-1-yl)methyl]-1H-1,3-imidazole (bmi) has three potential N-atom donors and can act in monodentate or bridging coordination modes in the construction of complexes. In addition, the bmi ligand can adopt different coordination conformations, resulting in complexes with different structures due to the presence of the flexible methylene spacer. Two new complexes, namely bis{1-[(benzotriazol-1-yl)methyl]-1H-1,3-imidazole-κN3}dibromidomercury(II), [HgBr2(C10H9N5)2], and bis{1-[(benzotriazol-1-yl)methyl]-1H-1,3-imidazole-κN3}diiodidomercury(II), [HgI2(C10H9N5)2], have been synthesized through the self-assembly of bmi with HgBr2or HgI2. Single-crystal X-ray diffraction shows that both complexes are mononuclear structures, in which the bmi ligands coordinate to the HgIIions in monodentate modes. In the solid state, both complexes display three-dimensional networks formed by a combination of hydrogen bonds and π–π interactions. The IR spectra and PXRD patterns of both complexes have also been recorded.

Controlled Growth and Self-Assembly of CaCO3 Superstructures between the Organic-Water Interfaces

2010 ◽  
Vol 434-435 ◽  
pp. 597-600
Author(s):  
Xiao Hong Liang ◽  
Jun Hui Xiang ◽  
Fu Shi Zhang ◽  
Li Xing ◽  
Bo Song ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Calcium Carbonate ◽  
Self Assembly ◽  
Crystallization Behavior ◽  
Gas Diffusion ◽  
The Self ◽  
Assembly Process ◽  
X Ray Diffraction ◽  
X Ray ◽  
Scanning Electron

In this paper, the crystallization behavior of calcium carbonate between the organic-water interfaces using a slow gas-diffusion procedure is studied. The organic-water interfaces can control the crystallization of calcium carbonate to form a flower-shaped superstructure. The precipitates of calcium carbonate were identified by X-ray diffraction (XRD) and scanning electron microscopy (SEM). A possible mechanism about the self-assembly process of CaCO3 crystals has been analyzed. It is found that the morphology of CaCO3 superstructure depends on the properties of organic solvent. This paper also presents the influence of surfactant monolayer, between the biphase interfaces, on the CaCO3 superstructure. This study suggests that it is possible to control morphogenesis of calcium carbonate by a combination of a surfactant monolayer with the organic-water interfaces.

Fabrication of Nanosheets and Micro-Spheres from the Self-Assembly and Polymerization of N-Octadecyltrichlorosilane

2011 ◽  
Vol 311-313 ◽  
pp. 485-488 ◽  
Author(s):  
Shuai Zhang ◽  
Qing Ping Ke ◽  
Lei Zhang ◽  
Tian Di Tang
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Self Assembly ◽  
Micelle Formation ◽  
The Self ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Hydrolysis Process ◽  
Scanning Electron

Formation of layered nanosheets and micro-spheres from a simple self-assembly and polycondensation of n-octadecylsilane (PODS) in water and toluene is demonstrated, respectively. The structure of the micro-spheres was characterized by Scanning Electron Microscope (SEM), Transmission Electron Microscopy (TEM) and X-ray Diffraction (XRD). According to the TEM images, it was firstly confirmed that the micro-spheres consist of stacks of bilayered polymerized n-octadecylsilane with head-to-head arrangements. The co-effects of water and solvent were proposed to control the octadecyltrichlsilane hydrolysis process and eventually the morphology of the micro-spheres. A micelle formation mechanism for the formation of the PODS micro-spheres under the co-effects of water and solvent were firstly proposed.

scholarly journals Urethane tetrathiafulvalene derivatives: synthesis, self-assembly and electrochemical properties

2015 ◽  
Vol 11 ◽  
pp. 2343-2349 ◽  
Author(s):  
Xiang Sun ◽  
Guoqiao Lai ◽  
Zhifang Li ◽  
Yuwen Ma ◽  
Xiao Yuan ◽  
...  
Keyword(s):  
Self Assembly ◽  
Driving Forces ◽  
Noncovalent Interactions ◽  
Electronic Conductivity ◽  
The Self ◽  
Stacking Interactions ◽  
X Ray Diffraction ◽  
X Ray ◽  
Hydrogen Bond Interactions ◽  
Better Than

This paper reports the self-assembly of two new tetrathiafulvalene (TTF) derivatives that contain one or two urethane groups. The formation of nanoribbons was evidenced by scanning electron microscopy (SEM) and X-ray diffraction (XRD), which showed that the self-assembly ability of T 1 was better than that of T 2 . The results revealed that more urethane groups in a molecule did not necessarily instigate self-assembly. UV–vis and FTIR spectra were measured to explore noncovalent interactions. The driving forces for self-assembly of TTF derivatives were mainly hydrogen bond interactions and π–π stacking interactions. The electronic conductivity of the T 1 and T 2 films was tested by a four-probe method.

The Preparation of Comb Polymer Rotaxanes and Study on their Self-Assembly Behavior

2016 ◽  
Vol 852 ◽  
pp. 653-656
Author(s):  
Li Sun ◽  
Lin Zhu ◽  
Jun Peng Xie ◽  
Rui Fang Guan
Keyword(s):  
Self Assembly ◽  
Inclusion Compound ◽  
Life Science ◽  
Molecular Assembly ◽  
The Self ◽  
X Ray Diffraction ◽  
X Ray ◽  
H Nmr ◽  
Self Assembling ◽  
Assembly Behavior

It is very important to form a stable, structure-controlled material by molecular assembly inthe fields of materials and life science. How cyclodextrins affect the self–assembly behavior of inclusion compounds becomes the focus recently, due to the advantages of selectivity, regulating, capability, biocompatibility and other interesting properties. In thispaper, polyoxyethylene ω-tristyrylphenyl methacrylate (SEM-25) and α-cyclodextrin (α-CD) form inclusion compound (AS) firstly, then copolymer of AS and methyl methacrylate (MMA) - the comb-like polyrotaxanes (CD-PR) were prepared through the redox initiationsystem of free radical polymerization. Furthermore, the self-assembling behavior of CD-PR is studied, it is found that solvent has an great impact on aggregation morphology of CD-PR without changing composition of the polyrotaxanes. Products were characterized by X-ray diffraction (XRD), nuclear magnetic resonance (1H NMR) and scanning electron microscope (SEM).

scholarly journals Self-assembly of metallosupramolecular rhombi from chiral concave 9,9’-spirobifluorene-derived bis(pyridine) ligands

2014 ◽  
Vol 10 ◽  
pp. 432-441 ◽  
Author(s):  
Rainer Hovorka ◽  
Sophie Hytteballe ◽  
Torsten Piehler ◽  
Georg Meyer-Eppler ◽  
Filip Topić ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Nmr Spectroscopy ◽  
Single Crystal ◽  
Self Assembly ◽  
The Self ◽  
Assembly Process ◽  
X Ray Diffraction ◽  
X Ray ◽  
Pyridine Ligands ◽  
Racemic Form

Two new 9,9’-spirobifluorene-based bis(4-pyridines) were synthesised in enantiopure and one also in racemic form. These ligands act as concave templates and form metallosupramolecular [(dppp)2M2L2] rhombi with cis-protected [(dppp)Pd]2+ and [(dppp)Pt]2+ ions. The self-assembly process of the racemic ligand preferably occurs in a narcissistic self-recognising manner. Hence, a mixture of all three possible stereoisomers [(dppp)2M2{(R)-L}2](OTf)4, [(dppp)2M2{(S)-L}2](OTf)4, and [(dppp)2M2{(R)-L}{(S)-L}](OTf)4 was obtained in an approximate 1.5:1.5:1 ratio which corresponds to an amplification of the homochiral assemblies by a factor of approximately three as evidenced by NMR spectroscopy and mass spectrometry. The racemic homochiral assemblies could also be characterised by single crystal X-ray diffraction.

Sign in / Sign up

Export Citation Format

Share Document