scholarly journals Self-assembly of heteroleptic dinuclear silver(i) complexes bridged by bis(diphenylphosphino)ethyne

2018 ◽  
Vol 47 (3) ◽  
pp. 946-957 ◽  
Author(s):  
Sarah Keller ◽  
Timothy N. Camenzind ◽  
Johannes Abraham ◽  
Alessandro Prescimone ◽  
Daniel Häussinger ◽  
...  
Keyword(s):  
Self Assembly ◽  
The Self ◽  
X Ray ◽  
X Ray Crystallography

The self assembly of Ag[PF6], bis(diphenylphosphino)ethyne and a bpy or tpy ligand was studied in solution using 31P–109Ag HSQC spectroscopy and by X-ray crystallography.

Self-Assembly of a Charge-Neutral Molecular Square

2004 ◽  
Vol 57 (5) ◽  
pp. 409 ◽  
Author(s):  
Mohammad Akbar Ali ◽  
Paul V. Bernhardt ◽  
Chong Lee Kiem ◽  
Aminul Huq Mirza
Keyword(s):  
Molecular Weight ◽  
Solid State ◽  
Self Assembly ◽  
1H Nmr Spectroscopy ◽  
The Self ◽  
State Structure ◽  
X Ray ◽  
X Ray Crystallography ◽  
A Charge ◽  
Molecular Square

Complexation of cadmium(II) by the ditopic (bis-tridentate) thiocarbazone ligand 1,5-bis(6-methyl-2-pyridyl- methylene)thiocarbonohydrazide, H2L1, results in the self-assembly of a charge-neutral 2 × 2 molecular grid, [Cd4(L1)4], comprising four metals and four ligands in an interlocked cyclic array. The solid-state structure of this tetramer has been established by X-ray crystallography and in solution by 1H NMR spectroscopy. The presence of lower molecular weight oligomers was identified by both NMR and ESI-MS.

Synthesis and aggregation properties of boron-dipyrromethene dyes conjugated with guanine units

2018 ◽  
Vol 22 (09n10) ◽  
pp. 944-952 ◽  
Author(s):  
Fen Li ◽  
Yongjie Zhang ◽  
Lina Zhou ◽  
Xin Zhang ◽  
Zhijian Chen
Keyword(s):  
Self Assembly ◽  
Solvent Polarity ◽  
The Self ◽  
X Ray ◽  
X Ray Crystallography ◽  
H Nmr ◽  
Nmr Study ◽  
Vis Spectroscopy ◽  
G Quadruplex ◽  
Boron Dipyrromethene

Two boron-dipyrromethene dyes bearing a conjugated guanine unit (G-BODIPYs) 1 and 2 were synthesized and fully characterized. The self-assembly properties of these dyes were investigated by X-ray crystallography, [Formula: see text]H NMR and UV-vis spectroscopy. As revealed by X-ray crystal structure studies, G-BODIPY 1 self-assembled into ribbon-like structures due to the intermolecular hydrogen bonding and [Formula: see text]–[Formula: see text] stacking interaction. Concentration-dependent [Formula: see text]H NMR experiments confirmed the formation of hydrogen bonds of the guanine units in solution for both dye 1 and 2. In the presence of K[Formula: see text], the characteristic signals for the formation of cyclic G-quadruplex structures were observed in the [Formula: see text]H NMR study. Aggregation of G-BODIPY dyes was further monitored by UV-vis absorption spectroscopy by varying the solvent polarity and temperature. H-type aggregates of dye 1, which was characterized by a new hypsochromically shifted absorption band with [Formula: see text] 461 nm, was obtained. In the presence of K[Formula: see text], the enhancement of stability was observed for the H-aggregates of dye 1.

Flexibility in the Self-Assembly of Silver Complexes: Coordination Polymers from Multi-Armed Pyridylmethyleneoxy Ligands

2013 ◽  
Vol 66 (4) ◽  
pp. 443 ◽  
Author(s):  
Peter J. Steel ◽  
Christopher M. Fitchett
Keyword(s):  
Coordination Polymers ◽  
Self Assembly ◽  
Pyridine Ring ◽  
Relative Orientation ◽  
The Self ◽  
Silver Complexes ◽  
X Ray ◽  
Precise Nature ◽  
X Ray Crystallography

The syntheses of new silver complexes of five isomeric bis(pyridylmethyleneoxy)benzenes, differing in the position of substitution on the benzene and pyridine rings, and three isomeric 1,3,5-tris(pyridylmethyleneoxy)benzenes, differing in the position of substitution on the pyridine ring, are described. The structures of six of these complexes were characterised using X-ray crystallography, showing the formation of coordination polymers for 3-pyridyl- and 4-pyridyl-armed ligands and discrete complexes for 2-pyridyl-armed ligands. The precise nature of the structure was further determined by the relative orientation of the pyridine rings in each case.

Following the self assembly of supramolecular MOFs using X-ray crystallography and cryospray mass spectrometry

2010 ◽  
Vol 1 (1) ◽  
pp. 62 ◽  
Author(s):  
Georg Seeber ◽  
Geoffrey J. T. Cooper ◽  
Graham N. Newton ◽  
Mali H. Rosnes ◽  
De-Liang Long ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Self Assembly ◽  
The Self ◽  
X Ray ◽  
X Ray Crystallography

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.

Examining the structure of the mature amyloid fibril

2002 ◽  
Vol 30 (4) ◽  
pp. 521-525 ◽  
Author(s):  
O. S. Makin ◽  
L. C. Serpell
Keyword(s):  
Self Assembly ◽  
Rational Design ◽  
Amyloid Fibrils ◽  
Structural Information ◽  
X Ray ◽  
X Ray Crystallography ◽  
Cryo Electron Microscopy ◽  
Fibre Diffraction ◽  
Complementary Techniques ◽  
Mature Fibril

The pathogenesis of the group of diseases known collectively as the amyloidoses is characterized by the deposition of insoluble amyloid fibrils. These are straight, unbranching structures about 70–120 å (1 å = 0.1 nm) in diameter and of indeterminate length formed by the self-assembly of a diverse group of normally soluble proteins. Knowledge of the structure of these fibrils is necessary for the understanding of their abnormal assembly and deposition, possibly leading to the rational design of therapeutic agents for their prevention or disaggregation. Structural elucidation is impeded by fibril insolubility and inability to crystallize, thus preventing the use of X-ray crystallography and solution NMR. CD, Fourier-transform infrared spectroscopy and light scattering have been used in the study of the mechanism of fibril formation. This review concentrates on the structural information about the final, mature fibril and in particular the complementary techniques of cryo-electron microscopy, solid-state NMR and X-ray fibre diffraction.

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.

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