Two one-dimensional d¹⁰-metal coordination polymers based on polydentate Schiff-base ligand: synthesis, crystal structure and luminescent properties

Template effect of innocent and coordinating anions on the formation of interpenetrated 2D and 3D networks: methyl orange and iodine sorption studies

A pyridyl based Schiff base resulted in a 2D staircase network (CP1) with Cd(ii) when ClO₄⁻ is the counter anion while the use of benzene-1,3-disulphonate counter anion resulted in a novel 3D Cd(ii) coordination polymer with threefold interpenetration (CP2).

Biologically active and thermally stable polymeric Schiff base and its metal polychelates: Their synthesis and spectral aspects

New metal polychelates of Mn(II), Co(II), Ni(II), Cu(II) and Zn(II) obtained by the interaction of metal acetates with polymeric Schiff base containing formaldehyde and piperazine, have been investigated. Structural and spectroscopic properties have been evaluated by elemental analysis, FT-IR and (1)H-NMR. Geometry of the chelated polymers was confirmed by magnetic susceptibility measurements, UV-Visible spectroscopy and Electron Spin Resonance. The molecular weight of the polymer was determined by gel permeation chromatography (GPC). Thermogravimetric analysis indicated that metal polychelates were more thermally stable than their corresponding ligand. All compounds were screened for their antimicrobial activities against Escherichia coli, Staphylococcus aureus, Bacillus subtilis, (bacteria) and Candida albicans, Microsporum canis, Cryptococcus neoformans (fungi) by agar well diffusion method. Interestingly, the polymeric Schiff base was found to be antimicrobial in nature but less effective as compared to the metal polychelates. On the basis of thermal and antimicrobial behavior, these polymers hold potential applications as thermally resistant antimicrobial and antifouling coating materials as well as antimicrobial packaging materials.

Cubane-type {M4O4} (M = CoII, ZnII, CuII) clusters: synthesis, crystal structures, and luminescent and magnetic properties

Three cubane-type {M₄O₄} clusters were synthesized and characterized. Their luminescent and magnetic properties were investigated.

Syntheses, crystal structures and photophysical properties of Ag(I) coordination complexes

Three Ag(I) coordination complexes, [Ag(pyzca)]n (1) (Hpyzca=pyrazine-2-carboxylic acid), Ag[(HNA)(NA)(H2O)4] (2) (HNA=nicotinic acid) and [Ag1Ag2-(2,3-pydc)]n (3) (H2pydc=pyridine-2, 3-dicarboxylic acid) have been synthesized by the hydrothermal method. Their structures are determined by single-crystal X-ray diffractometer. Complex 1 possesses the 3D infinite structure. Complex 2 is a mononuclear coordination complex and exhibits one 3D infinite network by a large number of hydrogen bonds. In complex 3, two crystallographic independent Ag(I) ions exist, i.e., Ag1 is three-coordinate and Ag2 is two-coordinate, forming the 2D layer structure. At room temperature in the solid state, the IR, FP and UV-Vis spectra of all complexes were measured and investigated in detail. The emission and absorption spectra of the three complexes and their corresponding ligands are compared and analyzed.

Bis(2-{[(9H-fluoren-2-yl)methyl-idene]amino}-phenolato-κ(2)N,O)zinc methanol disolvate

In the title compound, [Zn(C(20)H(14)NO)(2)]·2CH(3)OH, the Zn(II) atom lies on a crystallographic twofold rotation axis and is coordinated by two O atoms and two N atoms from two bidentate 2-{[(9H-fluoren-2-yl)methyl-idene]amino}-phenolate ligands within a distorted tetra-hedral geometry. The dihedral angle between the two chelate rings is 82.92 (5)°. In the coordinated ligand, the phenol ring is twisted at 30.22 (9)° from the mean plane of the fluorene ring. In the crystal, O-H⋯O hydrogen bonds link the complex mol-ecules to the methanol solvent mol-ecules.