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The synthesis of a series of compounds are made where M-Mo or W, L = a thienyl, or terthienyl carboxylate, and L are corresponding thienyl dicarboxylate. The electronic absorption spectra are reported and show intense metal-to-ligand charge transfer bands.

The redox reactivity of edge-shared bioctahedral (ESBO) (Re2 mu-NCS 2 NCS 8)3- is determined by electrochemical and spectroelectrochemical studies. The dirhenium complex undergoes reversible oxidation and one-electron reduction to yield stable species (Re2 mu-NCS 2 NCS 8)2- and (Re2 mu-NCS 2 NCS 8)4- of similar structure. Further redox reactions result to more reactive species, while two-electron reduction of (Re2 NCS 10)4- yields a new structural conformation in the direct metal-metal-bonded complex (Re2 NCS 8 NCS 2)6- which re-oxidizes back to (Re2 NCS 10)4-.

A spectroscopic study of the tetramethylammonium pentaselenide and hexaselenide complexes reveals the five prominent selenium sites in (NMe4)2Se5 and the three crystallographically different selenium sites in (NMe4)2Se6. The anionic conformation of (NMe4)2Se5 is identical in solid and solution state. The shielding anisotropies for the alpha and beta selenium sites are larger than for the gamma site.

Se solid-state NMR spectra with cross-polarization and magic-angle spinning on (M(Se4)(sub 2))(super 2-) complexes with (Me(sub 4)N)+ and (Et(sub 4)N)+ facilitate the calculation of main constituents of Se77 shielding tensor from spinning sideband intensities. Structural changes in the (M(Se4)(sub 2))(super 2) geometry with cations between (Et4N)+ and (Me4N)+ complexes manifest in Se(77) isotropic chemical shifts.

15N solid-state NMR measurements are undertaken on complexes of platinum(II) and platinum(IV) with two different amine ligands, including 15N-enriched 1,2-diaminoethane and the quadridentate ligand 3,7-diazanonane-1,9-diamine. Results indicate that the effective oxidation state of the metal atom influences the 15N chemical shift and J coupling to 195Pt. Moreover, in Pt(II), Pt(IV) and mixed-valence complexes, the Pt atom environemt becomes more alike as the specie changes from chloro to bromo to iodo.

The electronic and resonance Raman spectra of dirhodium tetrathiocarboxylate complexes are compared with those of their tetracetate analogues. A red (bathochromic) shift in the blue region and a lower wavenumber for the rhodium-rhodium stretching fundamental indicate longer and weaker Rh-Rh bonds for the tetrathiocarboxylate than for the tetraacetate complex. These results are consistent with earlier evidence from X-ray crystallographic studies.

Mo2L6 compounds where L = NMe2 and O(super t)Bu, react with (S,S,S)-triisopropanolamine (2 equiv) in benzene to yield Mo(sub 2)[(OC-)S)-HMeCH(sub 2)(sub 3)N](sub 2) as a blue crystalline solid. The calculated singlet-singlet transition energies are compared with those implicit in the observed electronic spectrum.

Cyclic voltagram of (Re2(NCS)10)(3-) reveals that the electrochemistry of this compound involves various redox reactions, spectrochemical studies of which indicate that the edge shared bioctahedral structure of the parent molecule is retained in (Re2(NCS)10)(Z-), where Z is 1, 2 or 4, and that the couples (Re2(NCS)10)(2-/3-) and (Re2(NCS)10)(3-/4-) are chemically reversible at room temperature. X-ray studies of (Re(NCS)8)(2-) reveals a direct metal-metal bond, wherein a weakly bound ligand occupies the axial position.

Reports on nuclear magnetic resonance (NMR) spectra results for [NMe4]2Se5 and [NME4]2Se6 selenide complexes. Isotropic chemical shifts; Single-crystal X-ray structure determinations.

Investigates by 77Se solid-state NMP spectroscopy the properties of [M(Se4)2]2- anions [Me4N]+ (M = Zn, Cd, Hg) and [Et4N]+ (M = Cd, Hg). Differences between the 77Se isotropic chemical shifts observed for the [Et4N] and [Me4N]+ complexes.

Probes the reversible and irreversible redox processes displayed by (Re2(NCS)10)3- using voltammetric and in situ spectroelectrochemical techniques. Infrared and ultraviolet/visible spectroscopic data; Single scan infrared spectra of (Re2(NCS)10)z- complexes.