Experimental Spectroscopic and Theoretical Studies of New Synthesized Sulfonamide Derivatives

In this paper, two new Schiff bases (L-1 and L-2) derived from substituted salicylaldehyde and sulfamethoxazole/sulfisoxazole were synthesized. The synthesized structures were elucidated by experimental spectroscopic methods such as FT-IR, H-1-C-13 NMR, H-1, and C-13 shielding tensors, and elemental analysis. The theoretical vibrational modes and nonlinear optical (NLO) properties have been computed by DFT/B3LYP/6-311G(d,p) method. Theoretical H-1 and C-13 shielding tensors were calculated with GIAO methods in CDCl3 with same level of theory. The results have shown that there is perfect harmony between the calculated parameters and recorded experimental data. The first order hyperpolarizabilities of the new synthesized compounds are 201.79 and 113.14 times larger than that of urea (0.3728 x 10(-30) esu), respectively. According to evaluated results, the L-1 and L-2 present large nonlinear optical activity and are candidate molecules for nonlinear optical applications.