DFT and QTAIM analysis of fluorenol and fluorenone in molecular nanoelectronics.

This study investigates the electronic properties of Fluorenone (A) and Fluorenol (B) for potential applications in molecular nanoelectronics. Using Density Functional Theory (DFT), Quantum Theory of Atoms in Molecules (QTAIM), and Landauer transport theory, we analyze the impact of electric fields on their conductivity and structural stability. Fluorenone, characterized by its conjugated carbonyl group, demonstrates electron-withdrawing capabilities, whereas Fluorenol, with its hydroxyl group, exhibits tunable electronic properties through hydrogen bonding. Computational modeling at the CAM-B3LYP/6-311 + G level reveals that Fluorenol consistently exhibits a smaller HOMO-LUMO gap than Fluorenone, suggesting superior charge transport efficiency. Density of States (DOS) and UV-Vis spectrum confirm these trends. Additionally, under varying electric field intensities, both molecules exhibit structural stability with minor length variations, supporting their suitability for nanoelectronic applications. The I-V characteristics show that Fluorenol-based systems (Au-B-Au) demonstrate higher conductivity than Fluorenone-based systems (Au-A-Au), attributed to enhanced charge delocalization. Furthermore, Joule and Peltier's heating analysis confirms lower heat dissipation in Fluorenol, making it an ideal candidate for thermally stable nanoelectronic devices, including medical implants. Electron Localization Function (ELF) and Localized Orbital Locator (LOL) analyses further validate Fluorenol's superior charge transport properties. These findings highlight Fluorenol as a promising material for molecular wires and next-generation nanoelectronic applications.