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A peptide-based metal-organic framework (MOF), a metal peptide framework (MPF), constructed from an oligovaline peptide family is described. The MPFs are stable and have some internal porosity, which has made them a promising prototype for the further development of MPFs.

Research has been conducted on the transition metal complexes, terpy-nitrony-nitroxide and terpy-imino-nitroxide. The preparation of these complexes has been carried out and the results are reported.

Two new one-dimensional nickel(II) complexes were synthesized and characterized. The two complexes are similar and may be described as one-dimensional with double-azido-bridged ligands in end-to-end and end-on coordination alternatively, while the end-on moiety is almost identical for the two complexes, the end-to-end moiety is different in each structure.

The photochemical formation of ferrimagnetic chains from a pair of manganese complexes a and b of bis(hexafluoroacetylacetonato)manganese(II) coordinated with diazodi(4-pyridyl)methane in the cis and trans arrangements as repeating units was described. The two isomeric manganese derivatives were prepared individually and were found to have helical and zigzag chain structures. Irradiation of the dilute paramagnetic manganese complexes transformed the diazo groups to the triplet carbenes and formed extended ferrimagnetic chains containing photochemically generated 2p spins.

Diazodi-4-pyridylmethane, a new bridging ligand, has been prepared, with two functional groups, two pyridyl nitrogens and a diazo group. The crystal structure and magnetic properties of copper complex where interaction between the Cu(II) ion and the generated carbene was found to be ferromagnetic is reported. Temperature dependence of the magnetic susceptibility and magnetic interaction in a 1:2 complex of Cu(hfac)2 with diazophenyl-4-pyridylmethane was also considered.

Transmetalation (Ni/Pt system), C(sub enolate)-metal bond formation (Pd/Au system) or O(sub enolate)-metal bond formation (Ni/Co system) may occur between nickel- or palladium-coordinated phosphino enolate ligands and metal electrophiles. This was gleaned from an investigation of the reactions of phosphino enolates toward electrophilic metal reagents. The crystal structures of Pd-Au and Ni-Co complexes, which reveal a different chemoselectivity of the enolate moiety, are described.

The transition metal coordination compounds are prepared from 1,9-bis(3,5-dimethyl-1-pyrazolyl)-3,7-dithia-5-nonanol (Hbdnol), which acts as a pentadentate ligand. IR, ligand field spectroscopy and EPR reveal that Ni(bdnol)Cl3 exhibits ferromagnetic intramolecular interaction and an antiferromagnetic ordering between adjacent dimers. The dinculear copper complex are antiferromagnetically coupled and are EPR silent at room temperature. The syntheses of Co(bdnol)(NCS)3, Zn2(bdnol)Cl(NCS)2, Cu2(bdnol)(NO3)3 and Cu2(Hbdnol)(NCS)2 are discussed.

The synthesis and characterization of a new carboxylato-bridged [Co.sup.II]thiophenedicarboxylic acid (TDC) compound is presented. The title compound has shown an unprecedented asymmetric tetradentate coordination mode of the carboxylate functions and the magnetic measurements have shown weak ferromagnetic interactions between the Co ions within the dimers.

The structural and magnetic synthesis of a series of transition-metal molecular compounds resulting from the combination of 3-pyridine sulfonate-water heterocomplexation processes is reported. The overlap between magnetic orbitals of the complexes was modified at low temperature which influenced the spin polarization mechanism along the H-bonds resulting in different intermolecular magnetic interactions.

Density functional theory (DFT) based on hybrid functional and localized atomic type basis sets is employed for calculating the exchange couplings in the layered three-dimensional compound Cu2(OH)3NO3. The result helped in achieved a sound theoretical determination of a measurable quantity without resorting to any approximation on the nature and the range of magnetic interactions providing accurate values by considerably enriching the interpretation of the magnetic susceptibility.