Structural investigation of a new cadmium coordination compound prepared by sonochemical process: Crystal structure, Hirshfeld surface, thermal, TD-DFT and NBO analyses

A new nanostructured cadmium complex containing a tridentate Schiff base ligand was sonochemically synthesized and characterized by XRPD, FT/IR, NMR, and single crystal X-ray crystallography. Structural data showed that cadmium(II) ion is surrounded by three nitrogen atoms of Schiff base ligand and two iodide anions. The crystal packing was contained the intermolecular interactions such as CH⋯O, CH⋯I and π⋯π interactions organizing the self-assembly process. Hirshfeld surfaces and corresponding fingerprint plots have been used for investigation of the nature and proportion of interactions in the crystal packing. FT/IR, NMR and XRD data were in agreement with the X-ray structure and confirm the phase purity of the prepared sample. The molecular structure of the complex was optimized by density functional theory (DFT) calculation at the B3LYP/LANL2DZ level of theory and the results were compared with experimental ones. For more concise study of structure and spectral aspects of the complex, natural bond orbital (NBO) analysis and time-dependent density functional theory (TD-DFT) have been also performed. Thermal stability of the cadmium iodide complex was investigated by thermogravimetric analysis (TGA). Finally, cadmium oxide nanoparticles was prepared by direct calcination of CdLI₂ complex as a new precursor.

Sonication-assisted synthesis of a new cationic zinc nitrate complex with a tetradentate Schiff base ligand: Crystal structure, Hirshfeld surface analysis and investigation of different parameters influence on morphological properties

A nanostructured cationic zinc nitrate complex with a formula of [ZnLNO₃]NO₃ (where L = (N²E,N^2'E)-N¹,N^1'-(ethane-1,2-diyl)bis(N²-((E)-3-phenylallylidene)ethane-1,2-diamine)) was prepared by sonochemical process and characterized by single crystal X-ray crystallography, scanning electron microscopy (SEM), FT-IR and NMR spectroscopy and X-ray powder diffraction (XRPD). The X-ray analysis demonstrates the formation of a cationic complex that metal center is five-coordinated by four nitrogen atom from Schiff base ligand and one oxygen atom from nitrate group. The crystal packing analysis demonstrates the essential role of the nitrate groups in the organization of supramolecular structure. The morphology and size of ultrasound-assisted synthesized zinc nitrate complex have been investigated using scanning electron microscopy (SEM) by changing parameters such as the concentration of initial reactants, the sonication power and reaction temperature. In addition the calcination of zinc nitrate complex in air atmosphere led to production of zinc oxide nanoparticles.

Sonochemical synthesis and characterization of new seven coordinated zinc, cadmium and mercury nitrate complexes: New precursors for nanostructure metal oxides

The nitrate complexes of group 12 elements with a tridentate Schiff base ligand (L = (E)-N1-((E)-3- phenylallylidene)-N2-(2-((E)-((E)-3-phenylallylidene) amino)ethyl) ethane-1,2-diamine) were synthesized via sonochemical process and characterized by various physical and chemical methods. The structural analysis of the zinc nitrate complex by single crystal X-ray diffraction analysis shows that the central atom is seven-coordinated by three nitrogen atoms from the Schiff base ligand as well as four oxygen atoms from two different nitrate anions. The geometry around the metal center can be described as a distorted pentagonal bipyramid. The crystal packing analysis of zinc nitrate complex indicates that the intermolecular interactions related to nitrate groups plays the essential role in the orientation of supramolecular structure. Hirshfeld surfaces (HS) and their corresponding fingerprint plots (FP) have been also used for further investigation of crystal structure of zinc nitrate complex. Furthermore thermal analyses (TG/DTG) of three nanostructure complexes were carried out and discussed. Finally, direct thermolysis of zinc and cadmium nitrate complexes in air atmosphere led to the production of zinc and cadmium oxide nanoparticles.

Recurrent supramolecular motifs in discrete complexes and coordination polymers based on mercury halides: prevalence of chelate ring stacking and substituent effects

We report the synthesis, X-ray characterization and DFT study of five Hg(ii) complexes with Schiff bases containing a nicotinohydrazide core to explore the formation of chelate-ring π-stacking interactions.