Diamagnetic Anisotropy Measurements of Nematic Liquid Crystals

Three-dimensional blueprinting of molecular patterns in liquid crystalline polymers

“…The result (574 mT for 14µm thick cell) demonstrated good agreement (∼ 1% error) with the reported data in Ref. [89,46].…”

“…Elastic constants characterizing the nematic state can be calculated indirectly by measuring the critical field. [29][30][31] Once the magnetic anisotropy w a is measured separately, 32 the elastic constant can be calculated by using the eqn (1). Fig.…”

“…The result (574 mT for 14 μm thick cell) demonstrated good agreement (∼1% error) with the reported data in ref. 32 and 46. Based on the critical field values we were able to calculate the required magnetic field and De Gennes's magnetic coherence length 2 for different compositions and surfaces.…”

“…The critical field measurement can be a simple and effective method for estimation of Frank elastic constants [43,44,45]. Once the magnetic anisotropy χ a is measured separately [46], the elastic constant can be calculated by using the equation 6.1. The transition can be detected through observation of a sudden change in the intensity of the linearly polarized transmitted light.…”

A simple method to measure the twist elastic constant of a nematic liquid crystal

“…However, a big electromagnet is required in order to generate high magnetic field (~1 Tesla). Meanwhile, the magnetic susceptibility anisotropy (Δχ m ) [22] should be determined beforehand. Another approach is to use IPS cell, in which twist deformation can be induced by an electric field.…”