DFT molecular simulations for static, dynamic and solvent-dependent nonlinear optical properties of triphenylamine-carbazole-based organic dyes with D-D-A framework

Nonlinear optical (NLO) materials are vital for advancing cutting-edge optoelectronic technology. Herein, triphenylamine-carbazole-based organic dyes with a D-D-A framework are quantum chemically designed with acceptor modifications, and their geometric, electronic, static, dynamic, and solvent-dependent NLO properties are explored using density functional theory (DFT) simulations. The IEFPCM model is employed to investigate the solvent effect on the NLO properties of proposed compounds (BSA-1 to BSA-9). Interestingly, the dipole moment (mu tot), average linear polarizability (alpha tot), and first hyperpolarizability (beta tot) were determined for all proposed compounds in gas phase and water (e = 78.36), DMSO (e = 46.83), methanol (e = 32.61), tetrahydrofuran (e = 7.43), chloroform (e = 4.71), and benzene (e = 2.27) solvents. Natural population analysis (NPA), transition density matrix (TDM), UV-Vis investigation, frontier molecular orbital (FMO), and topological analysis (MEP, ELF, and LOL) were carried out to explain the NLO findings. The topological study suggests that BSA and BSA-1 to BSA-9 are chemically active and may have NLO implications. Moreover, the findings demonstrate that BSA-9 is the most promising second-order NLO candidate because of the highest lambda max (418.60 nm) in dichloromethane (DMF) and the lowest energy gap (1.49 eV) among all the derivatives. It was found that BSA-2 and BSA-9 demonstrated the giant static alpha o (7.26 x 102) and beta o (9.91 x 104) values among the proposed compounds for use in a wide range of solvent-dependent NLO applications. The solvent effect on NLO in all proposed compounds is noticeable, especially in BSA-9, which exhibited beta o = 1.89 x 105 in benzene, 2.80 x 105 in THF, 3.21 x 105 in methanol, 3.25 x 105 in DMSO and 3.28 x 105 in water. Furthermore, Electro-optical Pockels effect (EOPE) beta(-omega,omega,0) and the second harmonic generation (SHG) beta(-2 omega,omega,omega) results computed at omega = 532 nm (0.0856 au) and omega = 1064 nm (0.0428 au) frequencies confirm that all proposed compounds are excellent NLO candidates and should be targeted for future static, frequency-dependent and solvent-dependent NLO applications.

Automated summary

This study explores the nonlinear optical properties of triphenylamine-carbazole-based organic dyes and their dependence on solvents. The results suggest that these compounds have significant potential for nonlinear optical applications, with BSA-9 being the most promising candidate. Furthermore, the solvent effect on the nonlinear optical properties is notable.