Electronic and Optical Materials

Many computers, such as laptops, have flat-panel screens or displays that contain liquid crystals (Bahadur 1990). Liquid crystals are composed of small semirigid molecules that are elliptical or oblong in shape and spontaneously orient, forming anisotropic fluids (Collings 1990). Liquid crystals commonly used in flat-panel displays have orientational order but do not have long-range positional order. The direction of the preferred orientation in a liquid 

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Larry E Thompson, Chemical Engineering Research Opportunities in Electronic and Optical Materials Research... 

Klavs F. Jensen, Chemical Engineering in the Processing of Electronic and Optical Materials A Discussion... 

In the solid, electrons reside in the valence band but can be excited into the conduction band by absorption of energy. The energy gap of various solids depends upon the nature of the atoms comprising the solid. Semiconductors have a rather narrow energy gap (forbidden zone) whereas that of insulators is wide (metals have little or no gap). Note that energy levels of the atoms "A" are shown in the valence band. These will vary depending upon the nature atoms present. We will not delve further into this aspect here since it is the subject of more advanced studies of electronic and optical materieds. 

Thus, important structure/property relationships are emerging that are relevant to electronic and optical materials applications for these materials. In a different vein, side chain crystallization has resulted in the first liquid crystalline inorganic and organometallic macromolecules, viz., unusual poly(dialkoxy-phosphazenes) described by Allcock (p. 250) and Singler (p. 268). 

In conclusion, radiation chemical matrix isolation technique gives precise information on the electronic structure of charge carriers, which is useful for the molecular design of organic semiconductors as electronic and optical materials. 

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