Syntheses, structures and properties of copper(II) and cobalt(II) metal–organic frameworks based on R-isophthalate (R=–CH3 or –C(CH3)3) and 1,1′-(1,4-butanediyl)bis(imidazole) ligands

Influence of ligand composition on crystal structure formation – isostructurality and morphotropism

The replacement of an H-atom with a Me-group leads to the isostructurality of polymeric Ag(i) complexes, whereas it causes morphotropic adjustments in the parent ligands (discrete molecules).

Conformational, electronic, and spectroscopic characterization of isophthalic acid (monomer and dimer structures) experimentally and by DFT

Isophthalic acid (C6H4(CO2H)2) is a noteworthy organic compound widely used in coating and synthesis of resins and the production of commercially important polymers such as drink plastic bottles. The effects of isophthalic acid (IPA) on human health, toxicology, and biodegradability are the main focus of many researchers. Because structural and spectroscopic investigation of molecules provides a deep understanding of interactional behaviors of compounds, this study stands for exploring those features. Therefore, the spectroscopic, structural, electronic, and thermodynamical properties of IPA were thoroughly studied in this work experimentally using UV-Vis, (1)H and (13)C NMR, FT-IR, FT-Raman and theoretically via DFT and TD-DFT calculations. The UV-Vis absorption spectrum in water was taken in the region 200-400nm. The NMR chemical shifts ((1)H and (13)C) were recorded in DMSO solution. The infrared and Raman spectra of the solid IPA were recorded in the range of 4000-400cm(-1) and 3500-50cm(-1), respectively. DFT and TD-DFT calculations were performed at the level of B3LYP/6-311++G(d,p) in determination of geometrical structure, electronic structure analysis and normal mode. The (13)C and (1)H nuclear magnetic resonance (NMR) spectra were estimated by using the gauge-invariant atomic orbital (GIAO) method. The scaled quantum mechanics (SQM) method was used to determine the total energy distribution (TED) to assign the vibrational modes accurately. Weak interactions such as hydrogen bonding and Van der Walls were analyzed via reduced density gradient (RDG) analysis in monomeric and dimeric forms. Furthermore, the excitation energies, density of state (DOS) diagram, thermodynamical properties, molecular electro-static potential (MEP), and nonlinear optical (NLO) properties were obtained.

Cu2+-doped zeolitic imidazolate frameworks (ZIF-8): efficient and stable catalysts for cycloadditions and condensation reactions

Condensations and cycloadditions can be catalyzed by newly synthesized Cu-doped zeolitic imidazolate frameworks (ZIFs). The catalysts were well characterized and reusable.