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Abstract: Two novel isostructure open frameworks of Ln(III), [Ln(L)(H2O)·1.5H2O] n , [Ln=Pr(1), Eu(2)], have been successfully synthesized using multifunctional organic compound 7,8,4′-tricarboxymethoxyisoflavone (L) as a linker through hydrothermal technique. Compounds 1 and 2 consist of 2D networks, which are further assembled into 3D architecture with 1D channels constructed by coordination bonds and the lattice water molecules array in lines occupying these voids via hydrogen bonds. In these compounds, L only exhibit one coordination mode coordinating to Ln(III), and four oxygen atoms from two carboxylate groups and two carboxymethoxy groups of one L coordinate to one Ln(III), simultaneously. The thermogravimetric analyses of these compounds show that the coordinated water and lattice water are lost in two steps, and the final residues are lanthanide oxides. [Copyright &y& Elsevier]

[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]