Theoretical investigation of the nonlinear optical properties of substituted anilines and N,N-dimethylanilines

► NLO properties of series of anilines and N,N-dimethylanilines were calculated. ► Dipole moment, polarizability, hyperpolarizability and optical band gap were examined. ► Studied effect of solvent, donor, acceptor, substituent and conjugation length. ► Strong donor-acceptor intramolecular charge transfer interaction most important. ► (CH3)2N as donor and vinyl nitro group para resulted in strongest β value.