Enhancement of NLO Properties in OBO Fluorophores Derived from Carbazole–Coumarin Chalcones Containing Carboxylic Acid at the N-Alykl Terminal End

Abstract

The nonlinear optical (NLO) properties of carbazole–coumarin-based chalcones and their OBO complexes of D−π–A and D−π–A−π–D types with carbazole as donor substituted with N-alykl chain at the 9 position with carboxylic acid end group are studied in detail. These dyes exhibit good emission solvatochromism. The NLO properties of dyes 5–8 were studied by two methods, namely, solvatochromic and computational method. The linear polarizability (α), hyperpolarizability (β), and second-order hyperpolarizability (γ) of dyes 5–8 were studied by time-dependent density-functional theory computational method using five different range-separated functionals, namely, CAM-B3LYP, HISSbPBE, HSEH1PBE, wB97, and wB97X, with triple ζ basis set 6-311++G­(d,p). The correlation between the NLO properties is well established with the geometry of the dyes by understanding the enhancement of hyperpolarizability, second-order hyperpolarizability, and two-photon absorption (TPA) properties of complexed and uncomplexed carbazole–coumarin chalcones experimentally and theoretically. The dye 8 showed maximum enhancement in the NLO properties like 167 GM two-photon absorption cross section in toluene, which is due to the effective charge transfer in the molecule owing to the presence of extra donor and rigidized planar conformation of the dye due to OBO complexation of the chalcone. Z-scan technique was used to study the third-order nonlinearity (χ(3)) of the dyes. The structure–property relationship has been well established in the studied dyes, which can act as better organic NLOphores.

A nonlinear optical switch induced by an external electric field: inorganic alkaline–earth alkalide

“…LiNbO 3 and KTiPO 4 ) 2 were widely used in commercial nonlinear optical (NLO) devices, NLO materials gained enormous attention and became an active research eld, owing to their broad applications. [3][4][5][6][7][8][9] Up to now, various types of strategies have been proposed to enhance (hyper)polarizability coefficients, i.e., designing organic molecules with a donor-acceptor architecture, 10,11 spin-polarization molecules with singlet diradical character, [12][13][14] importing diffuse excess electrons into a molecular system to form excess electron compounds, etc. Excess electron compounds have been proven to serve as potential candidates for NLO materials with excellent NLO responses.…”

“…57 On the other hand, NLO switches with a large difference in NLO properties in the presence of external stimulator triggering have attracted more and more attention in recent years, 19,20,50 because of their excellent potential applications in signal processing, data storage and optical frequency converters etc. [3][4][5][6][7][8][9] In the presence of EEF triggering, NLO switches of the organic electride molecule K(1)/calix [4]pyrrole/K(2) with b e 0 values ranging from 0 (EEF ¼ 0 (a.u.)) to 3.147 Â 10 6 (a.u.)…”

NLO Properties of 2‐Napthol Monoazo Disperse Dyes by DFT and Z‐Scan Technique – A Detailed Study

“…The theoretically observed values of first‐order hyperpolarizability (β) and second‐order hyperpolarizability (γ) for 2‐napthol azo dyes 1–4 are larger than the values for hyperpolarizability of urea . Moreover, the β and γ values of these dyes were compared with the reported donor‐π‐acceptor dyes . We found that β and γ values of these dyes are competes with the reported donor‐π‐acceptor dyes supplementary information (Table S30).…”

Pyrene Based NLOphoric D‐π‐A‐π‐D Coumarin‐Chalcone and Their Red Emitting OBO Difluoride Complex: Synthesis, Solvatochromism, Z‐scan, and Detailed TD‐DFT Studies

“…Patil et al., reported the NLO properties of D‐π‐A based 1‐(4‐bromophenyl)‐3‐(2, 4, 5‐trimethoxyphenyl) prop‐2‐en‐1‐one (2, 4, 5‐TMBC) by experimental method, later this experimental NLO properties explored theoretically by Muhammad et al . Recently, the NLO properties of D‐π‐A based coumarin‐chalcone studied experimental method and correlated theoretically by our research group …”

“…The coumarin derivatives are widely used in laser dyes, organic light emitting diodes (OLED), dyes sensitized solar cells (DSSC), cell‐imaging and optical brighteners . In recent years, the coumarin‐chalcone chromophores are widely studied for their NLOphoric properties . Coumarin‐chalcone shows solid‐state photoluminescence, AIE, second harmonic generation (SHG) properties, the high sensitivity of transition energy to the static electric field changes, good ICT in D‐π‐A .…”