Molecular self-assembly: diastereoselective synthesis and structural characterisation of a novel binuclear copper(i) double helicateIn memory of Professor Dr. Drs. h.c. mult. Alfred Rieche (1902–2001).

Nature creates exquisite molecular assemblies, required for the molecular-level functions of life, via self-assembly. Understanding and harnessing these complex processes presents an immense opportunity for the design and fabrication of advanced functional materials. However, the significant industrial potential of self-assembly to fabricate highly functional materials is hampered by a lack of knowledge of critical reaction intermediates, mechanisms, and kinetics. As we move beyond the covalent synthetic regime, into the domain of non-covalent interactions occupied by self-assembly, harnessing and embracing complexity is a must, and non-targeted analyses of dynamic systems are becoming increasingly important. Coordination driven self-assembly is an important subtype of self-assembly that presents several wicked analytical challenges. These challenges are “wicked” due the very complexity desired confounding the analysis of products, intermediates, and pathways, therefore limiting reaction optimisation, tuning, and ultimately, utility. Ion Mobility-Mass Spectrometry solves many of the most challenging analytical problems in separating and analysing the structure of both simple and complex species formed via coordination driven self-assembly. Thus, due to the emerging importance of ion mobility mass spectrometry as an analytical technique tackling complex systems, this review highlights exciting recent applications. These include equilibrium monitoring, structural and dynamic analysis of previously analytically inaccessible complex interlinked structures and the process of self-sorting. The vast and largely untapped potential of ion mobility mass spectrometry to coordination driven self-assembly is yet to be fully realised. Therefore, we also propose where current analytical approaches can be built upon to allow for greater insight into the complexity and structural dynamics involved in self-assembly.

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Self assembly in transition metal complexes: structural characterisation of the zinc carboxylate{bis(2-pyrrolecarboxylato)bis(1-methylimidazole)}zinc(II)

Polyhedron ◽

10.1016/s0277-5387(98)00047-3 ◽

1998 ◽

Vol 17 (13-14) ◽

pp. 2199-2206 ◽

Cited By ~ 7

Author(s):

Thomas A. Zevaco ◽

Helmar Görls ◽

Eckhard Dinjus

Keyword(s):

Transition Metal ◽

Metal Complexes ◽

Transition Metal Complexes ◽

Self Assembly ◽

Structural Characterisation

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Synthesis, Structural Characterisation and Self Assembly of Nanoparticles

10.26686/wgtn.17009300 ◽

2021 ◽

Author(s):

◽

John D. Watt

Keyword(s):

Lead Sulfide ◽

Self Assembly ◽

Palladium Nanoparticles ◽

Hydrogen Absorption ◽

Lead Chalcogenide ◽

X Ray ◽

Structural Characterisation ◽

Size And Shape ◽

Surfactant System ◽

Branched Nanostructures

<p>This thesis is concerned with the synthesis, structural characterisation and self assembly of various nanocrystalline materials. These materials include gold, lead sulfide and lead selenide with substantial focus given to the noble metal palladium. The aim of this research was to obtain size and shape control over nanoparticles formed from solution phase synthesis for various applications. This was realised with chemical techniques using organic surfactants as growth controlling agents. The morphology, composition, internal crystal structure and applicable properties of the as synthesised nanoparticles were fully investigated to give a complete characterisation. Characterisation was carried out using a number of techniques including Super and High Resolution Transmission Electron Microscopy (SHREM, HREM), Synchrotron Powder X-Ray Diffraction (XRD), Selected Area Electron Diffraction (SAED) and Energy Dispersive X-Ray Spectroscopy (EDS). The first chapter in this thesis focuses on the synthesis and self assembly of monodisperse gold nanoparticles into nanoparticle superlattices (NPSLs), an exciting new type of material. The nanoparticles were prepared using a well known chemical method at room temperature. They were then arranged into NPSLs by a simple evaporation technique. Intermediate structures to the SLs were isolated which gave an insight into their formation. This showed that the NPs first self assembled into an energetically unfavourable bilayer before forming the most thermodynamically preferred three dimensional structure. This behaviour was due to the presence of organic capping ligands. The second chapter is concerned with the synthesis and characterisation of lead chalcogenide nanoparticles (lead sulfide and lead selenide). These are semiconductor materials which can provide a photocurrent when illuminated with infra-red radiation which makes them ideal candidates for solar cell technology. The nanoparticles were synthesised using a bench top solvothermal method. By varying the nature of the surfactant system, the precursor and the reaction time and temperature a wide range of nanoparticles with different sizes and shapes were prepared. A type of lead sulfide nanoparticles was then chosen for capping ligand exchange experiments. The new method developed here provides a facile route to water soluble lead chalcogenide nanoparticles and a means to more easily extract a photocurrent when used in solar cell applications. The remainder of this thesis is focussed on the synthesis and structural characterisation of palladium nanoparticles. Palladium is a very important catalytic metal therefore control over its size and shape on the nanoscale is of primary concern. In the third chapter of this thesis various types of palladium nanoparticles were produced using solution phase techniques in a pressure reaction vessel. By varying the nature of the surfactant system, the precursor and the reaction pressure, temperature and time the size and shape of the resulting nanoparticles could be controlled. These included spherical and worm-like nanoparticles as well as novel pod-like and highly branched palladium nanostructures. These complex shapes were the first evidence of this kind of morphology for palladium and provide a new and exciting material for catalytic applications. The final chapter in this thesis features a full structural characterisation and growth mechanism for the novel, complex palladium nanostructures along with an investigation into their catalytic and hydrogen absorption properties. The structural characterisation of a palladium tripod provides the first direct evidence of complex growth from a symmetrical nanoparticle core possessing the face centred cubic crystal structure. The growth of the highly branched palladium nanostructures is then tracked in real time. It is shown that the growth involves the formation of nuclei followed by tripod intermediates and finally highly branched nanostructures. By varying the nature of the surfactant system the kinetics of the reaction and hence the morphology of the resulting nanostructures can be controlled. A full growth mechanism is therefore proposed. The catalytic activity of the highly branched palladium nanostructures towards a simple organic transformation reaction is investigated. Finally, the hydrogen absorption and desorption properties of the highly branched nanostructures is explored. The results presented here regarding palladium nanoparticles are applicable to other industrially important noble metals such as gold, silver and platinum. A final conclusion chapter is then presented along with ideas for future research.</p>

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Microfluidics for Time-Resolved Small-Angle X-Ray Scattering

10.5772/intechopen.95059 ◽

2020 ◽

Author(s):

Susanne Seibt ◽

Timothy Ryan

Keyword(s):

Self Assembly ◽

Structural Evolution ◽

Time Resolved ◽

X Ray ◽

Structural Characterisation ◽

X Ray Scattering ◽

Saxs Analysis ◽

Kinetics Of ◽

Ray Scattering

With the advent of new in situ structural characterisation techniques including X-ray scattering, there has been an increased interest in investigations of the reaction kinetics of nucleation and growth of nanoparticles as well as self-assembly processes. In this chapter, we discuss the applications of microfluidic devices specifically developed for the investigation of time resolved analysis of growth kinetics and structural evolution of nanoparticles and nanofibers. We focus on the design considerations required for spectrometry and SAXS analysis, the advantages of using a combination of SAXS and microfluidics for these measurements, and discuss in an applied fashion the use of these devices for time-resolved research.

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Self-assembly of non-macrocyclic triangular Ni3Ln clusters

Dalton Transactions ◽

10.1039/d1dt03742k ◽

2022 ◽

Author(s):

Tyson N Dais ◽

Rina Takano ◽

Takayuki Ishida ◽

Paul Plieger

Keyword(s):

Self Assembly ◽

Structural Characterisation ◽

Tetranuclear Complexes

The synthesis and structural characterisation of four new heterometallic tetranuclear complexes is reported. Three L3Ni3Ln type complexes, where Ln = La (C1), Eu (C2), and Gd (C3), have been fully...

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Gold-nanoparticle/organic linker films: self-assembly, electronic and structural characterisation, composition and vapour sensitivity

Faraday Discussions ◽

10.1039/b302678g ◽

2004 ◽

Vol 125 ◽

pp. 77-97 ◽

Cited By ~ 52

Author(s):

Yvonne Joseph ◽

Nadejda Krasteva ◽

Isabelle Besnard ◽

Berit Guse ◽

Miriam Rosenberger ◽

...

Keyword(s):

Gold Nanoparticle ◽

Self Assembly ◽

Structural Characterisation ◽

Organic Linker

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In vitro and in vivo polysaccharides assembly: ultrastructural and cytochemical study of growing plant cell wall components.

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100083035 ◽

1978 ◽

Vol 36 (2) ◽

pp. 434-435

Author(s):

D. Reis ◽

B. Vian ◽

J. C. Roland

Keyword(s):

Cell Wall ◽

Self Assembly ◽

Plant Cell Wall ◽

Higher Plants ◽

Three Dimensional ◽

Cytochemical Study ◽

Wall Components

Wall morphogenesis in higher plants is a problem still open to controversy. Until now the possibility of a transmembrane control and the involvement of microtubules were mostly envisaged. Self-assembly processes have been observed in the case of walls of Chlamydomonas and bacteria. Spontaneous gelling interactions between xanthan and galactomannan from Ceratonia have been analyzed very recently. The present work provides indications that some processes of spontaneous aggregation could occur in higher plants during the formation and expansion of cell wall.Observations were performed on hypocotyl of mung bean (Phaseolus aureus) for which growth characteristics and wall composition have been previously defined.In situ, the walls of actively growing cells (primary walls) show an ordered three-dimensional organization (fig. 1). The wall is typically polylamellate with multifibrillar layers alternately transverse and longitudinal. Between these layers intermediate strata exist in which the orientation of microfibrils progressively rotates. Thus a progressive change in the morphogenetic activity occurs.

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The Nature of Rapidly Extracted Phycocyanin from the Blue-Green Alga Plectonema Boryanum

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100065870 ◽

1971 ◽

Vol 29 ◽

pp. 366-367

Author(s):

M. Kessel ◽

R. MacColl

Keyword(s):

Self Assembly ◽

Analytical Ultracentrifugation ◽

Uranyl Acetate ◽

The Self ◽

Major Protein ◽

Subunit Structure ◽

Blue Green Alga ◽

Thin Sections ◽

Blue Green Algae ◽

Cacodylate Buffer

The major protein of the blue-green algae is the biliprotein, C-phycocyanin (Amax = 620 nm), which is presumed to exist in the cell in the form of distinct aggregates called phycobilisomes. The self-assembly of C-phycocyanin from monomer to hexamer has been extensively studied, but the proposed next step in the assembly of a phycobilisome, the formation of 19s subunits, is completely unknown. We have used electron microscopy and analytical ultracentrifugation in combination with a method for rapid and gentle extraction of phycocyanin to study its subunit structure and assembly.To establish the existence of phycobilisomes, cells of P. boryanum in the log phase of growth, growing at a light intensity of 200 foot candles, were fixed in 2% glutaraldehyde in 0.1M cacodylate buffer, pH 7.0, for 3 hours at 4°C. The cells were post-fixed in 1% OsO4 in the same buffer overnight. Material was stained for 1 hour in uranyl acetate (1%), dehydrated and embedded in araldite and examined in thin sections.

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