<i>In Silico</i> Investigation of Physicochemical and Nonlinear Optical Properties of Azobenzene-Based Novel Molecules

Novel nonlinear optical (NLO) molecules are designed in order to meet their tremendous demand in the field of optics and electronics. The first attempt of the structural tailoring of disperse orange 3 (DO3)-an azodye is made to develop nineteen derivative molecules (D1–D19). Two approaches were opted for preparing 4 groups of molecules. The first one was the extension of [Formula: see text]-conjugated system and the second strategy was the use of diverse electron donor and acceptor groups to develop unique donor-[Formula: see text]-acceptor systems. Density functional theory (DFT) calculations were performed for in silico characterization of the studied molecules. The polarizability ([Formula: see text] and first-order hyperpolarizability ([Formula: see text] values gave the insight of nonlinear optical response. All the designed molecules with extended conjugation and unique electron donor and acceptor group combination showed remarkably high [Formula: see text] and [Formula: see text] values. The highest hyperpolarizability value (42477.48 a.u.) with several thousand increases than [Formula: see text] (7113.25 a.u.) of reference DO3, was depicted by D19 of the designed derivatives. This can be attributed to greater intramolecular charge transfer (ICT) in it. Various interaction studies were made and global reactivity descriptors (GRDs) were calculated to determine their chemical nature and stability. The outcome of our study suggests that the designed molecules are potential candidates for NLO applications, like energy conversion for producing tunable lasers and high-resolution spectroscopic studies.