Nonlinear optical response of D-π-A chromophores based on benzoxazin: quantum modification of π‑spacer

Abstract

In this research article, four chromophores based on benzoxazine as the electron donor and tricyanovinyl dihydrofuran (TCF) as the electron acceptor have been designed to investigate the nonlinear optical (NLO) response. The geometric and electronic structures, absorption spectra, NBO analysis, and nonlinear optical response have been calculated by employing density functional theory (DFT) at PBEPBE/6-31G (d,p). The new design of chromophores has been proposed by the structural modification of π-spacers/conjugated systems. The DFT and TD−DFT computations at CAM−B3LYP/6−31G (d,p) have been performed to shed light on the influences of structural modification on the NLO properties. The absorption wavelength in different organic solvents, polarizability (α), and hyperpolarizability (β) are all determined. A strong NLO response indicates that this family of organic compounds with a D-π-A structure exhibits large first hyperpolarizability βtot values, these values are much greater than ones of urea. This theoretical model may be used to design other chromophores for usage in electro-optics.