Large second-harmonic generation (SHG) response and broad band gap are two important and competitive parameters. It is difficult to balance them out in one material. In this work, by coupling alkali earth metal (AEM) octahedra with large highest occupied molecular orbital (HOMO)−lowest unoccupied molecular orbital (LUMO) gap and nonlinear optical (NLO)-active tetrahedra units, nine noncentrosymmetric (NCS) compounds, belonging to a new quaternary chalcogenide family A I B 3 II C 3 III Q 8 VI with unique windmill-like [Mg 3 M 3 III Q 24 ] (M III = Al, Ga; Q = S, Se) units constructed by alternated [MgQ 6 ] octahedra and [M III Q 4 ] tetrahedra, are rationally designed and fabricated. The compounds show a stable structural framework but adjustable optical properties. Among them, NaMg 3 Ga 3 Se 8 shows a large SHG response (∼1 × AgGaS 2 (AGS)), wide band gap (in selenide) (2.77 eV), high laser-induced damage threshold (LIDT) (∼2.3 × AGS), and suitable birefringence (0.079@546 nm). It should be a potential candidate for infrared (IR) nonlinear optical (NLO) materials. The results enrich the chemical diversity of chalcogenides and open an avenue for the development of new IR NLO materials through the octahedra and tetrahedra coupled strategy.

Different surface planes of various types of TiO2 crystals have diverse catalysis effects on the splitting of H2O and H2 and the electronic structures of the formed hydroxylated titanium dioxide...

Plant diseases that are caused by fungi and nematodes have become increasingly serious in recent years. However, there are few pesticide chemicals that can be used for the joint control of fungi and nematodes on the market. To solve this problem, a series of novel 1,2,4-oxadiazole derivatives containing amide fragments were designed and synthesized. Additionally, the bioassays revealed that the compound F15 demonstrated excellent antifungal activity against Sclerotinia sclerotiorum (S. sclerotiorum) in vitro, and the EC50 value of that was 2.9 μg/mL, which is comparable with commonly used fungicides thifluzamide and fluopyram. Meanwhile, F15 demonstrated excellent curative and protective activity against S. sclerotiorum-infected cole in vivo. The scanning electron microscopy results showed that the hyphae of S. sclerotiorum treated with F15 became abnormally collapsed and shriveled, thereby inhibiting the growth of the hyphae. Furthermore, F15 exhibited favorable inhibition against the succinate dehydrogenase (SDH) of the S. sclerotiorum (IC50 = 12.5 μg/mL), and the combination mode and binding ability between compound F15 and SDH were confirmed by molecular docking. In addition, compound F11 showed excellent nematicidal activity against Meloidogyne incognita at 200 μg/mL, the corrected mortality rate was 93.2%, which is higher than that of tioxazafen.

The infrared and visible spectra of divalent metal complexes of OEP were obtained. The variations in precise absorbances for five metal-sensitive infrared bands at ca. 3050, 1230, 990, 920, and 750 cm-1 are examined as a function of macrocyclic conformation and metal-pyrrolic nitrogen (M-Np) bond distances. The exact positions of the bands at ca. 920,990,1230, and 3050 cm-1 are dependent on the M-Np bond distances. Additionally, the bands at 920,990, and 1230 cnr* 1 are dependent on the size of the lowest unoccupied pz orbital. The 1230-and 3050-cnr1 bands are sensitive to the macrocyclic conformation. In the visible region the variations in Xma, of the a and ß bands are also examined as a function of M-Np bond distance. These appear to be a function of the M-Np bond distance and size of the lowest unoccupied pz orbital. These findings are discussed in terms of stabilization of the a2u orbital on the porphyrin ligand. Implications for porphyrin reactivity are considered. 1988, 110, 3919.

Two new tellurite halides, CdPb2Te3O8Cl2 and Cd13Pb8Te14O42Cl14 with mixed cationic layered structures, have been synthesized by high-temperature solution method. CdPb2Te3O8Cl2 crystallizes in the noncentrosymmetric Aba2 space group, built by [CdPb2Te3O8]...