Structural, photophysical and optoelectronic activity of triphenylamine-based push–pull chromophores: a theoretical study

Triphenylamine was used as a donor and electron-withdrawing groups in different positions as terminal acceptor groups in order to design a series of push–pull chromophores (D1-5). The dyes were characterized via UV–vis spectroscopy and electric, absorption, and thermal studies. Based on the theoretical results, the electrochemical and optical investigations of D1-5 displayed reduced bandgap HOMO–LUMO energies. In addition, these compounds exhibited an electrical character, making them promising donor dyes for solar cell usage. The B3LYP/6-31G (d, p) basis set using the density functional theory (DFT) was applied in this study. The second-order NLO response was also investigated for D1-5 chromophores. D1-5 compounds have higher second-order nonlinear characteristics and a smaller HOMO–LUMO gap than electron-accepting groups ranging from ultraviolet to near-infrared. The thermodynamic properties were also calculated as a function of temperature in the 298.15 K range, including heat capacity, entropy, enthalpy, free energy, and zero-point energy. Graphical abstract