When liquid crystals were discovered way back in 1888, the molecules being examined were cholesterol derivatives. These phases were dubbed "cholesteric" liquid crystals, a name that has largely stuck. We now know that these are chiral nematic, denoted N* phases. The "*" is used in the field to denote chiral phases. The movie shown below is an attempt to capture the phase transition of an N* phase. For this experiment, the temperature was held at the clearing temperature; the LC and isotropic domains grow and shrink, largely because of air currents in the lab.
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Vance Williams
is a Professor of Chemistry at Simon Fraser University. Archives
October 2015
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