DFT investigation of the electronic structure and nonlinear optic properties (NLO) of 3-amino-4-(Boc-amino)pyridine

The molecular geometrical parameters, vibrational frequencies, electronic properties and nonlinear optical (NLO) behavior of 3-amino-4-(Boc-amino)pyridine have been evaluated using the B3LYP, CAM-B3LYP and B3PW91 levels of density functional theory (DFT). The dipole moment (μ) and first hyperpolarizability (β) values of the title complex show that the molecule can be a good candidate as NLO material. The energy of HOMO and LUMO levels and the HOMO–LUMO energy gap, hardness, softness and electronegativity have been analyzed using DFT/B3LYP method with the 6-31+G(d,p) basis set. To understand the effect of the different media (gas phase and in methanol solvent) in electronic transitions, the UV–Vis computations of the molecule have been performed using time-dependent DFT (TD-DFT)/6-31+G(d,p) by applying the integral equation formalism-polarized continuum model. The second-order interaction energies of 3-amino-4-(Boc-amino)pyridine have been calculated using natural bond orbital analysis.