Anopore confinement in the cyanobiphenyl-based liquid crystal dimer CB7CB. A dielectric study

We report an experimental work on the liquid crystal dimer 1'',7'-bis(4-cyanobiphenyl-4'-yl) heptane (CB7CB) confined to Anopore membranes. We have studied the behaviour of the dielectric relaxation modes in the isotropic (I), nematic (N) and twist-bend nematic (N-TB) phases by broadband dielectric spectroscopy and compared to the results of the bulk sample. We have found that the strength of the components of the static dielectric permittivity for bulk and confined samples diminishes when cooling but, once in the N-TB phase, those of the confined CB7CB tend to decrease in a slower rate compared to the ones of bulk CB7CB. This work is meant to play a humble tribute to the first report on a cyanobiphenyl-based LC in its 50(th) anniversary. [GRAPHICS]