A computational quantum chemical and polarizability calculations of liquid crystal 4-cyano-4-pentylbiphenyl with water molecule (H2O)

Abstract

In this paper, we investigate the quantum chemical parameters such as energy of the highest occupied molecular orbital (EHOMO), energy of the lowest unoccupied molecular orbital (ELUMO), HOMO-LUMO energy gap (△Egap), ionization potential (I), electron affinity (A), chemical potential (μ), electronegativity (χ), hardness (η), softness (S), and electrophilicity index (ω) of liquid crystal (LC) 4-cyano-4-pentylbiphenyl with water molecule (H2O). Above quantum chemical parameters have been calculated at Becke's three-parameter hybrid exchange functional and the Lee–Yang–Parr correlation functional (B3LYP) with 6-31G(d) and 6-31G++(d,p) basis sets in the framework of density-functional theory (DFT). For comparative purposes, we also optimize 4-cyano-4-pentylbiphenyl with water molecule at Perdew-Burke-Ernzerhof (PBEPBE) with 6-31++G(d,p) level. Mulliken charge analysis infer that (-0.03e) amount of charge is being associated with the H2O at B3LYP/6-31G(d) level. This fact indicates a considerable amount of electron population is transferred from pristine 4-cyano-4- pentylbiphenyl to H2O molecule. Polarizability tensor components such as αxx, αyy, αzz, average polarizability (αav), and polarizability anisotropy (Δα) have been calculated. The most intense IR spectral characteristics of 4-cyano-4-pentylbiphenyl with water molecule are accommodated in between 3000 cm−1 to 3920 cm−1at all presented levels.