Enhanced first-order non-linear optical responses of 4-amino-6-chloro-1,3-benzenedisulfonamide polymer

Abstract Polymers enriched with reactive sites and free-charge clouds have been a considerable field of research. The present study reports the nonlinear optical activity of polymer 4-amino-6-chloro-1,3-benzenedisulfonamide using density functional theory. The substitution of the sulfonamide group on the symmetrical positions gave rise to the intramolecular charge transfer within the title molecule. The molecular electrostatic potential surface illustrates that the O=S=O and NH 2 groups act as electrophilic and nucleophilic groups and were found responsible for the intramolecular charge transfer. This gave the dipole moment of 5.4 Debye for the title molecule. The molecular orbitals were used to compute the band gap of 3.81 eV. The value of hyperpolarizability was computed as 499.22 au. This value was found 27 times higher than the general reference nonlinear optical activity compound urea (18.53 au), four times higher than thiourea (102.3 au), and two times higher than phenyl urea (245.69 au). Thus, the reported study validates that the title molecule can be used as a potential NLO material.