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optical activity




rotation of the plane of polarization by an optically active substance
Optical activity demonstrated cane-sugar solution
The property, possessed by certain substances, of rotating the plane of polarization of polarized light passing through them. This optical rotation is measured by polarimetry. Optical activity is shown by asymmetric crystals which have two mirror-image forms – the rotation being to the left (laevorotatory, l-) or right (dextrorotatory, d-) respectively – and by compounds with asymmetric molecules showing optical stereoisomers. Magnetic rotation of the plane of polarizarion is known as Faraday rotation.


Related category

   • OPTICS AND OPTICAL PHENOMENA