Recent results on structural properties and possible bio-sensing applications of planar liquid crystal films are reviewed.

Bent-core (BC) materials that form nematic liquid crystals (BC nematics (BCNs)) are known only since 2000, but since then they have been intensively studied. In this review we give a comprehensive summary of the main research directions and results. After discussing representative examples of molecules making BCNs, we review theoretical predictions and experimental findings about macroscopic symmetries, such as chirality of achiral and chiral molecules, tetrahedratic symmetry and phase biaxiality versus uniaxiality. Then we describe the properties of smectic nano clusters often observed in BCNs, and discuss rheological properties that reveal unusually large viscosities and small twist and bend elastic constants. Finally, we focus on the electric properties of BCNs, such as dielectric and ferroelectric properties, electroconvection (EC) and electromechanical effects.

Considerable progress has been achieved in understanding the fascinating structure and physical properties of the ferroelectric liquid crystalline phases formed by bent-core liquid crystals (BLC). In this review, we discuss a manifold of polar structures and phases found in BLCs such as orthogonal and tilted ferro-/antiferroelectric phases, smectic phases, switchable columnar phases, modulated structures and phases stabilised by a periodic lattice of defects such as dark conglomerate and nanofilament phases. We review the theoretical aspects of ferroelectricity in BLCs including existing microscopic theories and computer simulations, polarity and chirality phenomena. The last part of the paper is devoted to the peculiarities of the behavior of BLCs in a restricted geometry (freely suspended films and filament) and the perspective technological applications.