Temperaturfunktionen der durch Mehrfachdotierung mit chiralen Verbindungen in einer nematischen Phase induzierten Helixganghöhe / Temperature Dependence of the Induced Helical Pitch of a Nematic Phase Using Several Chiral Additives

Abstract

Abstract A helix structure can be induced in nematic phases by adding chiral compounds. In general the helix pitch increases with temperature. It is shown that by using two suitable doping agents, each of which would give different senses of helix rotation when used individually, a particular temperature behaviour can be obtained. Depending on the concentrations, a temperature independent pitch, for example, or a helix inversion can be achieved. The results of experiments using the nematic phase N 4 (Merck) show good agreement with the theoretically predicted temperature dependence of the pitch.