Tetragonal Phase of 6-Oxoverdazyl Bent-Core Derivatives with Photoinduced Ambipolar Charge Transport and Electrooptical Effects.

Bent-core mesogens containing 6-oxoverdazyl radical as the angular central unit exhibit rich polymorphism that includes isotropic—isotropic transition, re-entant isotropic (lre), and a novel 3D tetragonal (Tet) phases. Surprisingly, the paramagnetic Tet phase interacts linearly with applied electric field and exhibits photoinduced ambipolar charge transport (µ ≈ 10-3 cm2 V-1 s-1). Magnetic analysis showed gradual increase of antiferromagnetic interactions upon cooling. [ABSTRACT FROM AUTHOR]