Liquid crystals A phase

Liquid crystal A phase that has the mobility of a liquid and some of the internal order of a crystal. It is also called a mesophase. 

Photoswitchable materials could be important components in molecular-scale electronic devices and several new systems have been reported. There have been other investigations of phototropic systems in which light is used to drive a reversible conformational change " or, in the case of liquid crystals, a phase transformation. Such photosystems are of interest for the engineering of microscopic photoactive devices but the subject is still in its infancy and practical devices remain elusive. Much more subtle is the use of light to trigger a change in... 

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