Preliminary communication Nematic-substrate repulsion in the nematic-isotropic phase coexistence region

Abstract

Observations of two types of nematic droplet in the nematic-isotropic phase coexistence region are reported. One type contains topological defects and is free to move within a thin, homeotropically treated cell; the other is defect free and appears to be pinned at the substrates. The freely moving droplet represents an apparently new liquid crystal-substrate repulsion, which depends on the director alignments at the substrate and at the surface of the nematic droplet.