Theoretical investigations on the structure and properties of p-n-alkoxy benzoic acid based liquid crystals

• Main Authors: Subhapriya, P., Dhanapal, V., Sadasivam, K., Vijayanand, P. S.
• Format: Conference Proceeding
• Language: English
• Subjects: Angles (geometry); BENZOIC ACID; BOND ANGLE; BOND LENGTHS; Charge density; CHARGE DISTRIBUTION; Charge transfer; Computer simulation; CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; Crystal structure; DENSITY FUNCTIONAL METHOD; Density functional theory; ELECTRON DENSITY; FOURIER TRANSFORMATION; Fourier transforms; HYDROGEN; Hydrogen bonds; INFRARED SPECTRA; INTERACTIONS; LIQUID CRYSTALS; Mathematical analysis; Molecular conformation; MOLECULES; Orbital stability; Organic chemistry; PHASE STABILITY; REACTIVITY; RELIABILITY; SIMULATION; Stability analysis; SURFACES
• ISSN: 0094-243X; 1551-7616
• DOI: 10.1063/1.4946647

The present study focused on the structural conformations, alkoxy chain lengths and mesogenic properties of two mole of alkoxy benzoic acid(nOBA) and one mole of suberic acid (SA) hydrogen bonded (nOBASA) complexes (n=8 to 10) by density functional theory (DFT) calculations and the Fourier Transform Infrared (FT-IR) spectrum. The intermolecular hydrogen bond formation was confirmed by the optimized geometric bond lengths and bond angles obtained by computation. Using the natural bond orbital (NBO) analysis, the stability of the molecule arising from hyper conjugative interactions and charge delocalization has been analyzed. Results obtained shows that the charge in electron density (ED) in σ*and π* antibonding orbital and second order delocalization energies E(2) authorizes the occurrence of intermolecular charge transfer. The molecular electrostatic potential (MEP) surface map is plotted over the optimized geometry of the molecule to obtain the chemical reactivity of the molecule. From the local charge distributions, the mesomorphic behavior and the nematic phase stabilities for each of the molecule have been predicted. Finally the calculated result is applied to simulated infrared spectra of 8OBASA mesogens which shows good agreement with the observed spectra. The comparison of the theoretical results obtained with the experimental ones shows the reliability of this DFT method.