Spontaneous mirror symmetry breaking by formation of chiral structures from achiral building blocks and emergent polar order are phenomena rarely observed in fluids. Separately, they have both been found in certain nematic liquid crystalline phases; however, they have never been observed simultaneously. Here, we report a heliconical arrangement of achiral molecules in the ferroelectric nematic phase. The phase is thus spontaneously both polar and chiral. Notably, the pitch of the heliconical structure is comparable to the wavelength of visible light, giving selective reflection controllable by temperature or application of a weak electric field. Despite bearing resemblance to the heliconical twist-bend nematic phase, this chiral ferroelectric nematic phase arises from electrical interactions that induce a noncollinear orientation of electric dipoles.

The design, synthesis and physicochemical properties of the highly polar ferroelectric nematic liquid crystal are reported. This compound exhibits enantiotropic N _F phase, as the very first example with such behaviour.

This research introduces a novel liquid crystal molecular design approach based on the para-sexiphenyl (6P) structure. Six new liquid crystalline materials were synthesized, incorporating an alkyl terminal and lateral substitutions of the sexiphenyl core to achieve temperature-stable and broad nematic phases. The synthetic pathway involved cross-coupling, resulting in derivatives with strong nematogenic characteristics. Optical investigations demonstrated that the tested material had high birefringence values, making it promising for optical and electronic applications. These results open up new avenues of research and offer potential practical applications in electronics, photonics, optoelectronics and beyond.

Understanding how heteroatom identity determines competing functional properties is essential for the rational design of multifunctional organic materials. Here, we report the synthesis of nine new chalcogenophene-based compounds in which oxygen, sulfur, or selenium is systematically incorporated into both the rigid core and terminal substituents. This homologous and isosteric molecular platform enables direct correlation of mesomorphic organization, photophysical response, and third-order nonlinear optical behavior within a single structural framework. We demonstrate that chalcogen substitution induces distinct and competing regimes of molecular self-assembly and excited-state electronic response. Thiophene-containing cores promote robust nematic mesophase formation (e.g., a nematic range of ~80 °C), whereas oxygen-containing derivatives favor ecicient radiative decay and enhanced third-order nonlinear optical response, yielding rare deep-blue emission with high fluorescence quantum yields up to 0.60 and color coordinates approaching the Rec.709 standard. Third-harmonic generation (THG) measurements in PMMA thin films at 1064 nm reveal χ⁽³⁾ values up to 12.34 × 10^-22 m² V^-2 , highlighting a regime in which high emission eciciency can coexist with strong third-order response despite limited mesomorphism. In contrast, increased chalcogen polarizability does not translate into simultaneous optimization of mesomorphic, emissive, and nonlinear properties.Terminal thioalkyl substitution consistently enhances fluorescence eciciency across the series. Quantum-chemical analysis reveals that these trends arise from a balance between electronic delocalization, backbone planarity, and excited-state reorganization, rather than polarizability alone, establishing transferable structure-property design principles for multifunctional organic materials.