Organic compounds future prospects

The text is divided into three parts. The first deals with the basic principles underlying the environmental behavior and effects of organic pollutants the second describes the properties and ecotoxicology of major pollutants in reasonable detail the last discusses some issues that arise after consideration of the material in the second part of the text, and looks at future prospects. The groups of compounds represented in the second part of the book are all regarded as pollutants rather than simply contaminants, because they have the potential to cause adverse biological effects at realistic environmental levels. In most cases these effects have been well documented under environmental conditions. The term adverse effects includes harmful effects upon individual organisms, as well as effects at the level of population and above. 

The prospective applications ofmolecular assemblies seem so wide that their limits are difficult to set. The sizes of electronic devices in the computer industry are close to their lower limits. One simply cannot fit many more electronic elements into a cell since the walls between the elements in the cell would become too thin to insulate them effectively. Thus further miniaturization of today s devices will soon be virtually impossible. Therefore, another approach from bottom up was proposed. It consists in the creation of electronic devices of the size of a single molecule or of a well-defined molecular aggregate. This is an enormous technological task and only the first steps in this direction have been taken. In the future, organic compounds and supramolecular complexes will serve as conductors, as well as semi- and superconductors, since they can be easily obtained with sufficient, controllable purity and their properties can be fine tuned by minor adjustments of their structures. For instance, the charge-transfer complex of tetrathiafulvalene 21 with tetramethylquinodimethane 22 exhibits room- temperature conductivity [30] close to that of metals. Therefore it could be called an organic metal. Several systems which could serve as molecular devices have been proposed. One example of such a system which can also act as a sensor consists of a basic solution of phenolophthalein dye 10b with P-cyciodextrin 11. The purple solution of the dye not only loses its colour upon the complexation but the colour comes back when the solution is heated [31]. 

Nevertheless, the need for systems having even better optoelectronic properties to be used in applications has driven researchers in materials science to develop novel compounds and novel structures. As the results of such activity the advances in organic material science have generated a vital and growing interest in organic materials research which could potentially revolutionize future electronic applications. The current development prospects of organic materials are, however, mostly limited in their scope to relatively low-performance areas. One of the reasons for this is, for instance, the low mobility of charge carriers. 

Schmidt, T.C., Zwank, L., Berg, M.E.M., Meckenstock, R.U., Haderlein, S.B. (2004) Compound-specific stable isotope analysis of organic contaminants in natural environments a critical review of the state of the art, prospects, and future challenges. Anal. Bioanal. Chem., 378, 283-300. 

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