Magnetic-Field Induced Isotropic to Nematic Liquid Crystal Phase Transition

We report on measurements of magnetic-field induced nematic order in the bent-core liquid crystal 4-chlororesorcinol bis[4-(4-$n$-dodecyloxybenzoyloxy) benzoate]. Using the 31 T solenoid at the National High Magnetic Field Laboratory, we have observed, at temperatures less than 1° above the clearing point, a first-order transition to the nematic phase. The critical magnetic field at which this occurs increases with temperature. We discuss these results within the context of both Maier-Saupe and Landau–de Gennes mean-field models for the nematic-isotropic transition. The implications of possible tetrahedratic order are also discussed. To our knowledge, this is the first observation of such a magnetic-field induced transition in a thermotropic liquid crystal; the reasons for which this behavior is now attainable are discussed.