Second- and third-order nonlinear optical properties of mono-substituted terpenoid-like chalcones

Two-Photon Absorption and Multiphoton Excited Fluorescence of Acetamide-Chalcone Derivatives: The Role of Dimethylamine Group on the Nonlinear Optical and Photophysical Properties

“…In previous years, the incorporation of electron-withdrawing (EW) and electron-donating (ED) groups in organic molecules’ backbones has been driving a great variety of biological, photonic, and optoelectronic applications [ 1 , 2 , 3 , 4 , 5 , 6 ], owing to the ability of such groups to enhance the linear and nonlinear optical of the organic structure [ 7 ]. A well-known example of this molecular structure is EX-π-EX, where X can be a withdrawing or donating group and π is the organic backbone.…”

“…Chalcones, also known as α, β-unsaturated ketones, are present in an extensive range of optical applications, such as second harmonic generation [ 8 , 9 , 10 , 11 , 12 , 13 ], holographic recording technology [ 14 ], and photorefractive polymers [ 15 ], to name a few. In addition, owing to the intrinsic structural flexibility, functionality, and electron mobility of chalcones, modulation of third-order nonlinearities has been explored [ 1 , 2 , 4 , 16 , 17 ]. Moreover, when strong EW/ED groups are attached to the chalcone backbone, a high emissive state may be created, allowing applications involving DNA or metal ion detection [ 18 ].…”

Optimization of Spatial Arrangement and Optical Nonlinearity of Chalcone Crystals by Halogen Substituted Donor Groups

“…With the continuous exploration of organic nonlinear materials, researchers found that the crystals of the chalcone system have the characteristics of high transparency, large laser damage threshold, good crystallinity, high nonlinear absorption coefficient, and extinction coefficient, and are of great research value. − The chalcone molecule has a large π-conjugated system and thus has a long charge transfer axis, and the intramolecular charge can be rapidly transferred from the donor to the acceptor, resulting in a large second harmonic generation (SHG) efficiency, , is the focus of current research. In order to obtain chalcone crystals with large nonlinear coefficients, the introduction of strong electron donors and acceptors is an effective design method. − Since halogen atoms have strong electron-withdrawing and electron-donating effects at the same time, multiple secondary bonds can be formed in the molecule, which can effectively induce the arrangement of the crystal structure and produce a large first-order super conversion rate. − Therefore, it is very valuable to design new second-order nonlinear crystals by introducing halogen elements in the donor.…”