Chromophores light-induced molecular response

Chromophores and their light-induced molecular response... 

The protonated Schiff base of 11-cis-retinal (PSBll) is the chromophore in the visual receptor rhodopsin. A light-induced cisitrans isomerization of the chromophore triggers the primary event in vision, which is a series of conformational changes of the protein. This photoreaction is considered as the archetype of a chemical reaction optimized by nature to achieve a specific molecular response. Hence, it was in focus of numerous computational and experimental investigations. 

Some chemical substances have been used in the past as switches to control ion transport. Several new molecular sensory devices, which are responsive crown ethers used for the dynamic control of cation and anion binding induced by changes in pH, redox potential, temperature, light, and magnetic and electrical field, have been developed. These new ligands possess chromophores or fluorophores linked to the macrocycle, and display drastic variations in their photochemical and/or luminescent properties upon cation complexation. 

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