Priyanka Kumari, Bijaya Basnet, Maxim Lavrentovich, and Oleg Lavrentovich have published an article in the journal Science on chiral ground states of ferroelectric liquid crystals. An object is considered chiral if it can be distinguished from its mirror image. Chirality is a characteristic of living organisms and is usually caused by chiral chemical structure of constituent molecules. The work by Priyanka Kumari, Bijaya Basnet and others, published in Science on March 22, describes structural chirality in a recently discovered ferroelectric nematic liquid crystal formed by polar molecules that are not chemically chiral.
Figure. Polarizing microscopy texture of the left-handed and right-handed chiral domains (left) and a scheme of left-handed and right-handed twists of electric polarization in neighboring chiral domains.
A thin film of a ferroelectric nematic spontaneously splits into domains of alternating left-handed and right-handed twists of the electric polarization. These domains are chiral and optically active and can be easily seen under an optical microscope with polarizers. The twists of electric polarization within the chiral domains reduce the electrostatic energy. The study illustrates that the underlying cause of chiral structure could be polar ordering of molecules that have no chemically induced chiral centers. The paper can be downloaded from the Science website.