Investigation on molecular organization and physical studies on asymmetric bent-core Liquid crystals

Abstract

A typical bent-core (BC) banana-shaped molecule consists of a relatively rigid bentcore part which has two rod-like arms joined end to end with an angle of about 120 degrees between them. In addition, exible aliphatic chains usually are attached to one or both ends of the rigid core of the molecule. Based on the rigid-arms and associated chain lengths, BC molecules can be classi ed into two categories: symmetric and asymmetric BC molecules. In a symmetric BC banana-shaped molecule, both the arms and the chains are the same, giving rise to C2V point symmetry of the molecule. However, in a asymmetric BC molecule, the asymmetry can be introduced either by using di erent chain lengths and linkage groups in the symmetric BC banana-shaped molecule or using rigid arms of di erent lengths. A bent-core hockey-stick shaped (BCHS) molecule is formed when one of the arms is relatively shorter than the other arm. The BCHS molecule can be considered to have an intermediate shape between the bent-core banana-shaped and the rod-like molecules