DFT study of GaAs quantum dot and 5CB liquid crystal molecule interaction

Liquid crystals (LC) are widely used in various optical devices due to their birefringence, dielectric anisotropy, and responsive behavior to external fields. Enhancing the properties of existing LCs through doping with nanoparticles, including semiconductor quantum dots, offers a promising route for improving their performance. Among various nanoparticles, QDs stand out for their high charge mobility, sensitivity in the near-infrared spectral region, and cost-effectiveness. These attributes make them ideal candidates for integration with LCs. While liquid crystalline behavior arises from the collective ordering of molecules, the microscopic interactions between QDs and LC molecules remain an intriguing area of study to understand the underlying quantum-level mechanisms. In this study, we employ Density Functional Theory to investigate the interaction between GaAs quantum dot and a 5CB molecule. The 5CB molecule and Ga atoms were brought together gradually, and the corresponding changes in interaction energy and electron density distributions were calculated. The energy profiles reveal a clear distance-dependent interaction, with a minimum observed at 2.1 Å, indicating the formation of stable complexes. While the BVP86 functional slightly overestimated the interaction energy, the B3LYP functional produced more accurate results, confirming the feasibility of stable quantum dot - 5CB molecule complexes.