Work

SANS study of partially fluorinated terphenyl liquid crystals under spatial confinement

Year: 2025

Type: article

Abstract: We report a small-angle neutron scattering (SANS) study of partially fluorinated terphenyl-based liquid crystals confined in anodic aluminium oxide (AAO) membranes with various pore diameters. The analysis combines structural imaging by scanning electron microscopy (SEM) with a scattering model that incorporates both the pores’ arrangement structure factor and a specific form factor, enabling quantitative insight into the spatial distribution of liquid crystalline material inside cylindrical nanochannels. In sufficiently narrow pores (20 and 40 nm), the confined liquid crystals exhibit paranematic ordering – a weakly anisotropic state induced by surface anchoring and geometric constraints – which is absent in 200 nm pores. The scattering length density profiles extracted from the data reveal a core–shell modulation, with significantly reduced density in the central region of the pore. The paranematic shell thickness is shown to depend on both pore size and molecular dimensions. These results provide a framework for interpreting soft-matter ordering under nanoconfinement and demonstrate the sensitivity of SANS to mesoscopic structural gradients in hybrid organic-inorganic systems.

Source: Journal of Molecular Liquids

DOI: 10.1016/j.molliq.2025.128895

Authors: Oleksandr Tomchuk, Anna Drzewicz, Adél Len, Vasyl Ryukhtin