Tetragonal phase of 6-oxoverdazyl bent-core derivatives with photoinduced ambipolar charge transport and electrooptical effects

J Am Chem Soc. 2014 Oct 22;136(42):14658-61. doi: 10.1021/ja507594h. Epub 2014 Oct 13.

Abstract

Bent-core mesogens containing 6-oxoverdazyl radical as the angular central unit exhibit rich polymorphism that includes isotropic-isotropic transition, re-entant isotropic (I(re)), 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) cm(2) V(-1) s(-1)). Magnetic analysis showed gradual increase of antiferromagnetic interactions upon cooling.