Synthesis, structural, spectroscopic and theoretical insights into a new malononitrile derivative: A candidate for nonlinear optical applications

• Published in: Journal of molecular structure Vol. 1319; p. 139312
• Main Authors: L, Vidya, Mangalassery, Shilpa, Raj, Aparna, M, Aparna V, S, Neelima, Joy, Monu, G, Anilkumar, Roymahapatra, Gourisankar, Naraharisetty, Sri Ram G, R, Anabha E, Sudarsanakumar, C
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 05-01-2025
• Subjects: DFT; Nonlinear optical properties; Single Crystal-XRD; Spectroscopy; Z)-2-(3-(4-bromophenyl)-3-chloroallylidene; Spectroscopy; Z)-2-(3-(4-bromophenyl)-3-chloroallylidene; DFT; Nonlinear optical properties; Single Crystal-XRD
• ISSN: 0022-2860
• DOI: 10.1016/j.molstruc.2024.139312

•A new NLO active allylidene malononitrile is synthesized.•The structure was confirmed using SC-XRD, 1H NMR, 13C NMR, and FTIR spectroscopy.•HOMO-LUMO energy were analysed using density functional theory (DFT).•Third-order nonlinear susceptibility highlighted the potential for NLO applications.
Functionalized alkylidene malononitriles play a crucial role as donor-acceptor molecules, exhibiting notable nonlinear optical (NLO) properties. Allylidene malononitriles, an analogue of alkylidene malononitriles, have not been explored before for their optical properties. The present work deals with the synthesis of (Z)-2-(3-(4-bromophenyl)-3-chloroallylidene) malononitrile using Knoevenagel condensation reaction of Z-3-(4-bromophenyl)-3-chloroacrylaldehyde and malononitrile. Structure of the compound was elucidated by single-crystal X-ray crystallography and related spectroscopic studies like FT-IR, NMR (1H, 13C), and UV–Vis spectroscopy, which were further supported with computational studies using Density Functional Theory (DFT) approach. The photoluminescence spectra showed that the compound exhibited an emission peak at 425 nm with an excitation wavelength of 352 nm. The single crystal study reveals that the compound belongs to a monoclinic system with space group P21/c. The thermal characteristics of the compound was analysed using TGA-DTA/DSC. Investigation of the third-order nonlinear susceptibility was done by femtosecond Z-scan technique and demonstrated the potential of phenyl-substituted allylidene malononitriles for its nonlinear optical applications. The observed positive lensing and strong reverse saturable absorption (RSA) at both visible (532 nm) and Near IR (800 nm) regions make this compound a promising candidate for optoelectronic applications.
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