Definition of optical activity in English:

optical activity

noun

Chemistry
  • [mass noun] The property (displayed by solutions of some compounds, notably many sugars) of rotating the plane of polarization of plane-polarized light.

    • ‘In the slightly different situation of a crystal with optical activity, the center of the bull's-eye is not black, and its color gives information about the amount of twist.’
    • ‘These materials are said to display optical activity, and are rapidly gaining popularity among engineers.’
    • ‘If the product and catalyst of a reaction were the same, then amplification of optical activity might just be possible, they reasoned.’
    • ‘Surprisingly no optical activity was found, even with a 100-fold magnification of the scale, although strong UV absorption was retained.’