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Two novel alkaline-earth zincophosphites, namely CaZn(HPO3)2 and Ba2Zn(HPO3)3, were successfully synthesized under hydrothermal conditions. CaZn(HPO3)2 exhibits a three-dimensional (3D) anionic framework with a 6-connected uni-nodal pcu α-Po primitive cubic topology, constructed by unique Zn2O8 dimers and HPO3 pseudo-tetrahedra, while Ba2Zn(HPO3)3 displays one-dimensional (1D) [Zn(HPO3)3]4− anionic chains. It is worth mentioning that CaZn(HPO3)2 represents the first example of an alkaline-earth zincophosphite compound with a 3D framework structure. Our research also revealed the importance of both alkaline earth cation sizes and Zn/P ratios in anionic open-framework formation. The crystal structures of both compounds were further verified by energy dispersive spectroscopy, IR spectroscopy and Raman spectroscopy. Optical diffuse reflectance spectra, coupled with Tauc's fitting, revealed direct bandgaps with energy values of 4.33 and 4.48 eV for CaZn(HPO3)2 and Ba2Zn(HPO3)3, respectively, which differ from the prediction of theoretical calculations. Density of states calculations were conducted to reveal the origin of the bandgaps and bond interactions. Both compounds exhibited moderate birefringence values. This work may have implications for the design and synthesis of novel metal phosphites with desired properties. [ABSTRACT FROM AUTHOR]

Galactaric acid (GA), an attractive biomass-based platform compound produced from galacturonic acid (GalA), has gained considerable attention in industry due to its application as a precursor for various polymers. Currently, GA is oxidized from galactose using nitric acid or GalA using bromine but its low selectivity and yield limit its industrial-scale production and application. The present study first sought to produce GA without any by-product from the monomeric compound of GalA obtained from pectin hydrolysis in an eco-friendly manner using Gluconobacter oxydans (G. oxydans) as the research object. In this regard, a wholly biological method was designed by combining enzymatic hydrolysis, electrodialysis, and resting-cell catalysis with pectin as a raw material to enhance its production. After a series of pectin degradation experiments, including degradation scheme screening and enzyme dosage and substrate concentration optimization, a pectin degradation rate of 96.9% was finally achieved. Furthermore, the resting-cell catalytic efficiency of the enzymatic hydrolysate purified by electrodialysis was consistent with that of the simulated solution, which was 20.7% higher than that of the untreated enzymatic hydrolysate. Additionally, the experiment confirmed that pH significantly influenced the catalytic and oxidative efficiency of resting-cell catalysis. Finally, 2520 mg L-1 of GA was stably produced by resting-cell catalysis in the broth at pH 4.0 for 72 h, suggesting it to be a promising green approach for industrial bio-production of GA. [ABSTRACT FROM AUTHOR]

A novel complex (C6H16N)3[Tb2(Hsal)3(NO3)6] (1) was synthesised and characterized using X-ray crystallography. The PXRD patterns indicate that complex 1 is stable after heating at 180 °C for half an hour. More interestingly, high luminescence quantum yields of 90%, 78%, and 53% and long lifetimes of 1.71, 1.72, and 1.71 ms were obtained at room temperature, 80 °C, and 180 °C, respectively. Thus, complex 1 is one of the rare examples of luminescent lanthanide complexes with both high luminescence efficiency and thermostability. [ABSTRACT FROM AUTHOR]

The new, quaternary diamond-like semiconductor (DLS) Cu4MnGe2S7 was prepared at high-temperature from a stoichiometric reaction of the elements under vacuum. Single crystal X-ray diffraction data were used to solve and refine the structure in the polar space group Cc. Cu4MnGe2S7 features [Ge2S7]6− units and adopts the Cu5Si2S7 structure type that can be considered a derivative of the hexagonal diamond structure. The DLS Cu2MnGeS4 with the wurtz-stannite structure was similarly prepared at a lower temperature. The achievement of relatively phase-pure samples, confirmed by X-ray powder diffraction data, was nontrival as differential thermal analysis shows an incongruent melting behaviour for both compounds at relatively high temperature. The dark red Cu2MnGeS4 and Cu4MnGe2S7 compounds exhibit direct optical bandgaps of 2.21 and 1.98 eV, respectively. The infrared (IR) spectra indicate potentially wide windows of optical transparency up to 25 μm for both materials. Using the Kurtz–Perry powder method, the second-order nonlinear optical susceptibility, χ(2), values for Cu2MnGeS4 and Cu4MnGe2S7 were estimated to be 16.9 ± 2.0 pm V−1 and 2.33 ± 0.86 pm V−1, respectively, by comparing with an optical-quality standard reference material, AgGaSe2 (AGSe). Cu2MnGeS4 was found to be phase matchable at λ = 3100 nm, whereas Cu4MnGe2S7 was determined to be non-phase matchable at λ = 1600 nm. The weak SHG response of Cu4MnGe2S7 precluded phase-matching studies at longer wavelengths. The laser-induced damage threshold (LIDT) for Cu2MnGeS4 was estimated to be ∼0.1 GW cm−2 at λ = 1064 nm (pulse width: τ = 30 ps), while the LIDT for Cu4MnGe2S7 could not be ascertained due to its weak response. The significant variance in NLO properties can be reasoned using the results from electronic structure calculations. [ABSTRACT FROM AUTHOR]

Eight ion-pair compounds, [1-APy]I3 (1), [o-FBz-1-APy]I3 (2), [o-ClBz-1-APy]I3 (3), [o-BrBz-1-APy]I3 (4), [m-FBz-1-APy]I3 (5), [m-ClBz-1-APy]I3 (6), [m-BrBz-1-APy]I3 (7) and [m-IBz-1-APy]I3 (8), were synthesized and characterized structurally. The melting point of 1, 2 and 5–8 is below 90 °C and hence these compounds can be used as ionic liquids. A common characteristic of the crystal structures of 1–8 is that the inorganic components form a linear I3− anion and the non-planar Schiff base cations surround the anion to form molecular stacks. There exist H⋯I hydrogen bond contacts between the cations and I3− anion in the eight compounds, and H⋯H interactions are the main force between the cations. The melting point of crystal 1 is the lowest with 64 °C among the eight compounds. 3 and 4 show higher Tm, ΔHfus and ΔSfus values. The substituent group of the Schiff base cation in the meta-position can also decrease the melting point of the compounds. In addition, Hirshfeld surface analysis was used to understand the intricacies of interactions occurring in the eight compounds, and the relationship between the melting point and the weak interaction was discussed. [ABSTRACT FROM AUTHOR]

Two novel alkaline-earth zincophosphites, namely CaZn(HPO 3 ) 2 and Ba 2 Zn(HPO 3 ) 3 , were successfully synthesized under hydrothermal conditions. CaZn(HPO 3 ) 2 exhibits a three-dimensional (3D) anionic framework with a 6-connected uni-nodal pcu α-Po primitive cubic topology, constructed by unique Zn 2 O 8 dimers and HPO 3 pseudo-tetrahedra, while Ba 2 Zn(HPO 3 ) 3 displays one-dimensional (1D) [Zn(HPO 3 ) 3 ] 4- anionic chains. It is worth mentioning that CaZn(HPO 3 ) 2 represents the first example of an alkaline-earth zincophosphite compound with a 3D framework structure. Our research also revealed the importance of both alkaline earth cation sizes and Zn/P ratios in anionic open-framework formation. The crystal structures of both compounds were further verified by energy dispersive spectroscopy, IR spectroscopy and Raman spectroscopy. Optical diffuse reflectance spectra, coupled with Tauc's fitting, revealed direct bandgaps with energy values of 4.33 and 4.48 eV for CaZn(HPO 3 ) 2 and Ba 2 Zn(HPO 3 ) 3 , respectively, which differ from the prediction of theoretical calculations. Density of states calculations were conducted to reveal the origin of the bandgaps and bond interactions. Both compounds exhibited moderate birefringence values. This work may have implications for the design and synthesis of novel metal phosphites with desired properties.

The new, quaternary diamond-like semiconductor (DLS) Cu 4 MnGe 2 S 7 was prepared at high-temperature from a stoichiometric reaction of the elements under vacuum. Single crystal X-ray diffraction data were used to solve and refine the structure in the polar space group Cc. Cu 4 MnGe 2 S 7 features [Ge 2 S 7 ] 6- units and adopts the Cu 5 Si 2 S 7 structure type that can be considered a derivative of the hexagonal diamond structure. The DLS Cu 2 MnGeS 4 with the wurtz-stannite structure was similarly prepared at a lower temperature. The achievement of relatively phase-pure samples, confirmed by X-ray powder diffraction data, was nontrival as differential thermal analysis shows an incongruent melting behaviour for both compounds at relatively high temperature. The dark red Cu 2 MnGeS 4 and Cu 4 MnGe 2 S 7 compounds exhibit direct optical bandgaps of 2.21 and 1.98 eV, respectively. The infrared (IR) spectra indicate potentially wide windows of optical transparency up to 25 μm for both materials. Using the Kurtz-Perry powder method, the second-order nonlinear optical susceptibility, χ (2) , values for Cu 2 MnGeS 4 and Cu 4 MnGe 2 S 7 were estimated to be 16.9 ± 2.0 pm V -1 and 2.33 ± 0.86 pm V -1 , respectively, by comparing with an optical-quality standard reference material, AgGaSe 2 (AGSe). Cu 2 MnGeS 4 was found to be phase matchable at λ = 3100 nm, whereas Cu 4 MnGe 2 S 7 was determined to be non-phase matchable at λ = 1600 nm. The weak SHG response of Cu 4 MnGe 2 S 7 precluded phase-matching studies at longer wavelengths. The laser-induced damage threshold (LIDT) for Cu 2 MnGeS 4 was estimated to be ∼0.1 GW cm -2 at λ = 1064 nm (pulse width: τ = 30 ps), while the LIDT for Cu 4 MnGe 2 S 7 could not be ascertained due to its weak response. The significant variance in NLO properties can be reasoned using the results from electronic structure calculations.