Synthesis, experimental and computational spectroscopic investigations of third-order nonlinear optical material (E)-N′-(benzo[d][1,3]dioxol-5-ylmethylene)benzohydrazide

An organic nonlinear optical material (E)-N′-(benzo[d][1,3]dioxol-5-ylmethylene)benzohydrazide (BDMB) has been successfully synthesized and characterized using spectroscopic techniques. Vibrational analysis has been carried out with the help of potential energy distributions to identify the functional groups. The ¹³C and ¹H-NMR chemical shift values are in good agreement with the theoretical results. Intramolecular stabilization by donor–acceptor interactions could be witnessed through natural bond orbital analysis. The one-electron excitation from the conduction band to the valence band was expressed by π–π ^* transition at 324 nm. The energy gap (3.96 eV) is calculated from the optical spectrum which explains the charge transfer mechanism of BDMB. The hyperpolarizability of the BDMB molecule is 30.8538  ×  10⁻³⁰ esu, which is 82 times greater than that of urea (β ₀  =  0.3728  ×  10⁻³⁰ esu). The third-order nonlinear absorption coefficient (β) and nonlinear refractive index (n ₂) are calculated to be 6.24  ×  10⁻⁵ cm W⁻¹ and 1.19  ×  10⁻⁹ cm² W⁻¹, respectively. Based on these points, BDMB can be projected with nonlinear properties for realizing new applications. (paper)