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As the main alkali and alkaline-earth oxides in red mud, the effects of Na 2 O and CaO on the physical properties, crystalline phases and microstructure of red mud based ultra-lightweight ceramsite (RUC) were systematically investigated using XRD, FTIR and SEM-EDS methods. Na 2 O and CaO promote the generation of glass phase and reduce the viscosity of liquid phase. A proper Na 2 O content accelerates the formation of internal large size pores and the expansion of ceramsite, but excessive Na 2 O makes the pores grow and connect to each other and then reduces the compressive strength of RUC. The presence of CaO produces the glass phase with high fluidity that can fill the internal pores of RUC, thereby reducing the expansion property and water absorption. High contents of Na 2 O and CaO accelerate the crystallization of nepheline and anorthite respectively, and the formation of anorthite is contributed to improve the strength of RUC. The bulk density and compressive strength of RUC can reach 365–485 kg/cm3 and 1.05–1.53 MPa when the contents of Na 2 O and CaO in RUC are controlled within 3% and 3.5%, respectively, which meet the requirement of GB/T 17431.2–2010. [ABSTRACT FROM AUTHOR]

[Display omitted] • Four-coordinate N-heterocyclic carbene (NHC) Cu(I) complexes with nonconjugated NHC ligand are synthesized and characterized. • The photophysical properties of the corresponding complexes is studied. • Complexes show deep blue emission in 452–466 nm region. • DFT and TDDFT calculations were employed to rationalize the photophysical properties. In the present study, a series of the four-coordinate N-hetercycle carbene (NHC) copper (I) complexes [Cu(MethyIm-Meth-benzTriazole)(POP)]PF 6 (P1), [Cu(BenzyIm-Meth-benzTriazole)(POP)]PF 6 (P2), and [Cu(BenzyBenzoIm-Meth-benzTriazole)(Xantphos)]PF 6 (P3), MethyIm-Meth-benzTriazole = 1-((1-benzyl-1 H -1,2,3-triazol-4-yl)methyl)-3-methyl-1 H -imidazolylidene, BenzyIm-Meth-benzTriazole = 1-((1-benzyl-1 H- 1,2,3-triazol-4-yl)methyl)-3-phenyl-1 H -imidazolylidene, BenzyBenIm-Meth-benzTriazole = 3-benzyl-1-((1-benzyl-1 H -1,2,3-triazol-4-yl)methyl)-1 H -benzo[d]imidazolylidene, POP = bis[(2-diphenylphosphino)phenyl]ether, have been synthesized and characterized. The molecular structure of P2 has been established by single-crystal X-ray diffraction study. The addition of the methylene spacer into the NHC ligand effectively breaks the π-conjugation of the ligand, resulting in a larger HOMO-LUMO energy gap. In the solid state, P1 – P3 exhibit deep blue emission in the range of 452–466 nm with the excited-state lifetimes (τ) of 14.9–16.2 μs and the emission quantum yields (Φ) of 8.50–11.9 % at room temperature. Additionally, the photophysical properties are explained by using density functional theory (DFT) and time dependent DFT. [ABSTRACT FROM AUTHOR]

In the present study, a series of the four-coordinate N-hetercycle carbene (NHC) copper (I) complexes [Cu(Ph-Im-cyPy)(Xantphos)]PF 6 (P1), [Cu(DimBenPh-Im-cyPy)(Xantphos)]PF 6 (P2), and [Cu(BenDimBenIm-CNPy)(Xantphos)]PF 6 (P3), Ph-Im-cyPy=3-benzyl-1-(4-cyano-pyridin-2-yl)-1 H -imidazolylidene, DimBenPh-Im-cyPy=3-(3,5-dimethylbenzyl-1-(4-cyano-pyridin-2-yl)-1 H -imidazolylidene, BenDimBenIm-CNPy=3-benzyl-1-(4-cyano-pyridin-2-yl)-1 H -5,6-dimethylbenzimidazolylidene, Xantphos=9,9-dimethyl-4,5-bis(diphenylphosphino)-9 H -xanthene, have been synthesized and characterized. The molecular structures of P1 – P3 have been established by single-crystal X-ray diffraction study. In the solid state, P1 – P3 exhibit orange-red emission in the range of 621–643 nm with shorter excited-state lifetimes (τ) of 5.73–6.42 μs and the emission quantum yields (Φ) of 1.0–3.9 % at room temperature. Additionally, the photophysical properties are explained by using density functional theory (DFT) and time dependent DFT. [Display omitted] [ABSTRACT FROM AUTHOR]

• The article we are going to contribute has the following highlights: • Two rare earth metal organic frameworks were synthesized by solvothermal method using zwitterionic 1,3-Bis(1-carboxylatoethyl)imidazolium bromide as ligand. • Complex 2 of Gd(C 9 H 11 N 2 O 4)(C 2 O 4)(H 2 O) (C 9 H 11 N 2 O 4 2‒ = 1,3-Bis(1-carboxylatoethyl) imidazolium ion, C 2 O 4 2- = oxalate) shows antiferromagnetic interactions in the temperature range 2−300 K. Good water-solubility, integrity and stability of 2 significantly different from common complexes grant it great potential in bio-related applications. Two rare earth coordination polymers named {[La 6 (C 9 H 11 N 2 O 4) 11 (H 2 O) 2 (OH) 2 ]⋅Br 5 } n (1) and [Gd(C 9 H 11 N 2 O 4)(C 2 O 4)(H 2 O)] n (2) (C 9 H 11 N 2 O 4 2‒ = 1,3-bis(1-carboxylatoethyl) imidazolium ion, C 2 O 4 2- = oxalate) were solvothermally synthesized using zwitterionic 1,3-bis(1-carboxylatoethyl)imidazolium bromide as ligand. 1 and 2 were both structurally characterized by single crystal X-ray diffraction, and their thermodynamic properties and magnetic properties of 2 were studied. In the 3D structure of 1 , La3+ ions are all ten-coordinated and exhibit three different coordination environments. This 3D structure of 1 is formed by La−O coordination bonds with Br− located in the cavities through H-bond and electrostatic attraction. Different from 1 , all Gd3+ ions in 2 have the same eight-coordinated environment. These two coordination polymers both have good thermostability until 323 °C for 1 and 375 °C for 2 , and then decompose giving rise to La 2 O 3 and Gd 2 O 3 , respectively. The magnetic behaviors of 2 are measured in the temperature range 2–300 K. [Display omitted] [ABSTRACT FROM AUTHOR]