Nanochemistry

Core Concepts in Supramolecular Chemistry and Nanochemistry Jonathan W. Steed, David R. Turner and Karl J. Wallace 2007 John Wiley Sons, Ltd ISBN 978-0 70-85866-0 (Hardback) 978-0470-85867-7 (Paperback) 

The bottom-up approach consists of the building up of nanomaterials from smaller building blocks. This approach has given rise to nanochemistry, typically with the use of self-assembly methods (see Chapter 3) for the formation of highly ordered two- and three-dimensional nanoscale structures. 

Nanotechnology The production of functional materials with features in the region of 0.1-500nm in size, i.e. nanoscale. 

Bottom-Up Approach The synthesis of nanoscale structures and devices by chemically building up from the molecular level. 

Top-Down Approach The use of microfabrication techniques that reduce bulk material into smaller components to form nanoscale features or objects. 

Fairbanks, Daniel J., and Andersen, W. Ralph (1999). Genetics The Continuity of Life. Pacific Grove, CA Brooks/Cole Publishing. 

Nelson, David L., and Cox, Michael M. (2000). lahninger Principles of Biochemistry, 3rd edition. New York Worth Publishers. 

Although nanochemical control was proposed decades ago, it was only recently that many of the tools necessary for studying the nanoworld were developed. These include the scanning tunneling microscope (STM), atomic force microscope (AFM), high resolution scanning and transmission electron microscopies, x rays, ion and electron beam probes, and new methods for nanofabrication and Uthography. 

Studies of nanochemical systems span many areas, from the study of the interactions of individual atoms and how to manipulate them, how to control chemical reactions at an atomic level, to the study of larger molecular assembhes, such as dendrimers, clusters, and polymers. From studies of assemblies, significant new structures—such as nanotubes, nanowires, three-dimensional molecular assembhes, and lab-on-a-chip devices for separations and biological research—have been developed. 

The ultimate frontier of nanochemistry is the chemical manipulation of individual atoms. Using the STM, single atoms have been assembled into larger structures, and researchers have observed chemical reactions between two atoms on a surface. The use of atoms as building blocks opens new 

9 Ozin, G. and Arsenault, A. Nano chemistry, Royal Society of Chemistry Cambridge, 2005. 

We can refer to the synthesis and study of chemical systems with features and functionality on the multi-nanometre length scale as nanochemistry and materials with features of size of the order of 

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The nanometer level of characterization is necessary for nanochemistry. We have learned from the history of once-new disciplines such as polymer science that progress in synthesis (production method) and in physical and chemical characterization methods are essential to establish a new chemistry. They should be made simultaneously by exchanging developments in the two areas. Surface forces measurement is certainly unique and powerful and will make a great contribution to nanochemistry, especially as a technique for the characterization of solid-liquid interfaces, though its potential has not yet been fully exploited. Another important application of measurement in nanochemistry should be the characterization of liquids confined in a nanometer-level gap between two solid surfaces, for which this review cites only Refs. 42-43. 

Ozin GA (1992) Nanochemistry Synthesis in diminishing dimensions. Adv Mater 4 612-649... 

Whitesides, G. M., Mathias, J. P. and Seto, C. T. (1991) Molecular self-assembly and nanochemistry a chemical strategy for the synthesis of nanostructures. Science, 254, 1312-1319. 

The prediction of stable structures that can be formed by groups of a few dozen atoms is computationally expensive because of the time required to determine the energy of each structure quantum mechanically, but such studies are increasingly valuable because of the need in nanochemistry to understand the properties of these small structures. The genetic algorithm is now widely used to help predict the stability of small atomic clusters.2... 

Supramolecular chemistry takes into consideration the weak and reversible non-covalent interactions between molecules, which include H-bond-ing, metal coordination, hydrophobic forces, van der Waals forces, n—n interactions, and covers different research fields, for example, molecular recognition, host-guest chemistry, mechanically interlocked and nanochemistry. 

As a perspective to this review, we conclude with recent developments in the use of whole cells to control the growth of nanopartides. Such approaches should allow one to take advantage of the whole cellular machinery and, combined with genetic engineering, appear very promising for the development of a green nanochemistry. 

In addition, it must be underlined that the chemical routes to cell-based materials are intrinsically green reactions because they imply that the viability of the living organisms is maintained. They should therefore be performed in mild temperature conditions and avoid the presence of cytotoxic products (or at least at non-toxic dose). Moreover, they use living cells that can be considered from a chemical reactivity point of view, as bio-renewable reagents. Such approaches can therefore be considered as the first steps towards the development of a green nanochemistry. 

Eric Bakker, Nanochemistry Research Institute, Department of Applied Chemistry, Curtin University of Technology, Perth, WA 6845, Australia... 

Steed, J. W. Turner, D. R. Wallace, K. J. Core Concepts in Supramolecular Chemistry and Nanochemistry , Wiley-VCH Weinheim, 2007. 

G. M. Whitesides, J. P. Mathias, C. T. Seto, Molecular Self-Assembly and Nanochemistry A Chemical Strat-... 

The study of principles relevant to building nanoscale structures of, for example, 1-100 nm in size has recently been referred to as nanoscience, and it is expected that methods for the fabrication of nanostructures will evolve into nanotechnologies. The present approach toward a nanochemistry is of more fundamental character since it is restricted to single molecules of a few nm in size or even smaller and focuses on the molecular pattern. 

The concept of nanochemistry which we are outlining herein implies four steps ... 

Nanochemistry has not yet advanced to a level where it can meet crucial technological require ments. The above examples, however, convincingly support the view of molecules as potential basic functional units. For a long time, so-called molecular electronics has been looked at as remote since... 

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