Influence of a Substituted Methyl on the Photoresponsive Third-Order Nonlinear-Optical Properties Based on Azobenzene Metal Complexes

Abstract

For studying the effect of a substituted group on the photoresponsive third-order nonlinear-optical (NLO) properties, photosensitive azobenzene derivative. Then H 2 L2 with a substituted methyl on the azobenzene ring was used to constructWhen the azobenzene moiety of the complexes is trans, the NLO behaviors of the complexes are the same. However, after the azobenzene moiety is excited by ultraviolet (UV) light to change from trans to cis, the substituted methyl increases the repulsion between two azobenzene rings in 3 and 4, thereby affecting their NLO behaviors. Therefore, the nonlinearity of the two types of complexes is different after UV irradiation. Density functional theory calculations support this result. The substituted methyl has a significant influence on the nonlinear absorption behaviors of 3 and 4. This work not only reports the examples of photoresponsive NLO materials based on metal complexes but also provides a new idea to deeply explore NLO properties.

Postsynthetic Modification of NU-1000 for Designing a Polyoxometalate-Containing Nanocomposite with Enhanced Third-Order Nonlinear Optical Performance

“…An example of the Z -scan OA mode is represented in Figure for the prepared samples at different incident power values. Eq was used to fit the experimental data and estimate the nonlinear optical absorption (NLA) coefficient, as shown in Table . , T norm ( z ) = L n ( 1 + q 0 false( z , t false) ) q 0 ( z , t ) …”

“…The third-order NLO (nonlinear optical) materials have attracted attention in various fields including harmonic generators, electro-optical signal processing, optical limiting and communications, saturable absorbers, lasers, optical switching, ultrafast photonics, and two-photon photodynamic therapy. − In this regard, the development of novel third-order NLO materials with improved performance is of crucial significance. , A number of strategies have been adopted to boost the third-order NLO susceptibility, with examples including the introduction of additional organic moieties with delocalization of electrons, , semiconductor doping of glasses, , and application of metallic nanoparticles to enhance surface plasmons. , Despite a long optical response time (pico-nanoseconds), the highest third-order NLO susceptibility (χ (3) (ω)) is typically observed for inorganic NLO materials. ,, However, the optical response time of polymeric and π-conjugated organic NLO materials lies in the femtosecond range in spite of their lower χ (3) (ω) values. − Numerous applications of NLO materials have motivated the research toward deep understanding of possible relationships between optical signals and chemical structures, ultimately aiming to find novel substances with a supreme nonlinear optical performance.…”

“… 1 − 3 In this regard, the development of novel third-order NLO materials with improved performance is of crucial significance. 4 , 5 A number of strategies have been adopted to boost the third-order NLO susceptibility, with examples including the introduction of additional organic moieties with delocalization of electrons, 6 , 7 semiconductor doping of glasses, 8 , 9 and application of metallic nanoparticles to enhance surface plasmons. 10 , 11 Despite a long optical response time (pico-nanoseconds), the highest third-order NLO susceptibility (χ (3) (ω)) is typically observed for inorganic NLO materials.…”

Efficient Strategy for Investigating the Third-Order Nonlinear Optical (NLO) Properties of Solid-State Coordination Polymers

“…In the third-order nonlinear optical (NLO) materials, coordination polymers (CPs) materials have attracted increasing attention because they can further adjust the NLO behaviors through coordination interaction based on the excellent third-order NLO properties of organic ligands. − Up to now, the third-order NLO properties of most CPs are studied in a liquid dispersion. To achieve feasible practical applications in a photonic device, CPs not only need to possess excellent third-order NLO performance but also require good processability to meet diverse scenario requirements. − Compared to a liquid dispersion, solid materials can be more easily processed and applied in devices without the risk of solvent leakage.…”

Regulation of Third‐Order NLO Properties by Central Metal Exchange of Heterogeneous MOFs@CeO2

“…[ 1–4 ] Metal–organic frameworks (MOFs) have attracted great attention in the development of the area due to their intriguing network topology, as well as modifying the functional linkers or even metal nodes can potentially enhance the synergy between individual frameworks which optimize the optical performance of the material. [ 5–11 ] In order to construct MOFs with excellent third‐order NLO properties, organic ligands with large conjugated systems or strong electron donor/acceptor groups are particularly important in regulating the efficiency of intermolecular electron transfer, and have been systematically elucidated over the past decades. [ 12–14 ] Varying metal ions or clusters with d‐electrons inside the frameworks also plays a dominant role in changing the level of d‐p electron transition in the MOFs skeleton and expand the π‐conjugate system to achieve the tuning effect of d‐p transition band.…”