Optical studies of the liquid crystal B2 phase formed by banana-shaped molecules - art. no. 041702

Null-transmission ellipsometry and depolarized light microscopy have been p erformed on free-standing films of three achiral banana-shaped compounds in the B2 phase. Our results support a two-layer unit cell previously propose d to explain the observed antiferroelectricity in thin films and bulk sampl es. We have studied thicker films than previously reported and have found n o deviations in the film structure from the earlier findings. Moreover, we can determine the layer spacing, the molecular tilt from the layer normal, and the three principal indices of refraction in the molecular reference fr ame.