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Syntheses, single crystal X-ray structural and spectroscopic characterizations are described for a variety of adducts of silver salts with ethylenethiourea (etu). [Ag.sub.2]S[O.sub.4]/etu (1:6) is isomorphous with its previously studied copper(I) counterpart, the [[Ag[(S-etu).sub.3]].sup.+] species disposed with their silver atoms on crystallographic 3-axes, one of the two independent cations being slightly perturbed by a distant O-sulfate approach along that axis. In AgCl/etu (1:3), the silver atom is in a four-coordinate ClAg[S.sub.3] environment, while AgN[O.sub.3]/etu (1:3) takes the form [[(etu).sub.2] Ag[(μ-S-etu).sub.2] Ag[(etu).sub.2]][(N[O.sub.3]).sub.2]. AgBr/etu (1:2) is binuclear [[(etu).sub.2]Ag(?-Br)2Ag(etu)2)], unlike its previously studied copper counterpart, which is [(etu)BrCu[(μ-S-etu).sub.2]CuBr(etu)]. AgCl/etu (4:6) is an interesting ionic polymer [[Cl[Ag.sub.4][(etu).sub.6]].sub.(∞|∞)[Cl.sub.3], containing a novel one-dimensional polymeric cation. Bands in the far IR spectra of these compounds are assigned to v(AgS) and v(AgX) (X = halogen) modes, and a correlation between v(AgS) and the Ag-S bond length d(AgS) is established for silver complexes involving the etu ligand. Key words: silver, sulfur ligands, X-ray crystal structure, coordination chemistry, complexes. On decrit les syntheses, les caracterisations spectroscopiques et par diffraction des rayons X d'une variete d'adduits de sels d'argent a l'ethylenethiouree (etu). L'adduit [Ag.sub.2]S[O.sub.4]/etu (1:6) est isomorphe avec sa contrepartie cuivreuse, Cu(I), etudiee anterieurement et les especes [[Ag[(S-etu).sub.3]].sup.+] sont disposees d'une facon telle que les atomes d'argent sont sur les 3-axes cristallographiques, l'un des deux cations independants etant faiblement perturbe par une approche distant du O-sulfate le long de cet axe. Dans le cas de l'adduit AgCl/etu (1:3), l'atome d'argent se trouve dans un environnement tetracoordine ClAg[S.sub.3], alors que le cas de l'adduit AgN[O.sub.3]/etu (1:3), prend la forme [[(etu).sub.2]Ag[(μ-etu).sub.2]Ag[(etu).sub.2]][(N[O.sub.3]).sub.2]. L'adduit AgBr/etu (1:2) est binucleaire [[(etu).sub.2]Ag[(μ-Br).sub.2]Ag[(etu).sub.2]], contrairement a sa contrepartie cuivreuse, Cu(I), etudiee anterieurement, qui est de la forme [(etu)BrCu[(mu]-S-etu).sub.2]CuBr(etu)]. L'adduit AgCl/etu (4:6) est un polymere ionique interessant [[Cl[Ag.sub.4][(etu).sub.6]].sub.(∞|∞)Cl3 qui contient un nouveau cation polymere monodimensionnel. On a attribue les bandes du spectre infrarouge eloigne aux modes v(AgS) et v(AgX) (X = halogene) et, pour les complexes impliquant un ligand etu, on a etabli une correlation entre v(AgS) et la valeur de la longueur de la liaison AgS, d(AgS). Mots-cles : argent, ligands sulfures, structure cristalline par diffraction des rayons X, chimie de coordination, complexes. [Traduit par la Redaction], Introduction Sulfur-donor ligands derivative of thiourea (tu) have been utilized in a variety of forms to access coordination complexes, most notably of type B or 'soft' metal ions. In its [...]

A study of the new compounds [NBu4][Cu(CN)X] (X = Br (I), I (2)) and [NBu4][Cu3(CN)(sub 4)].CH3CN (3) which are prepared by reaction of [NBu4]X with CuCN in acetone (1, 2) or acetonitrile (3) is presented. The results show that the solid-state structures contain (super 1)(sub infinity)[Cu(CN)X](super -) with infinite zigzag -Cu1-CN-Cu- chains in which each copper is bound to a halide ligand and the halide ion is only relatively weakly coordinated to the copper atom.

Research has been conducted on the Hg (sub)2 X (sub)2 compounds. The characterization of their solid-state (super)199 Hg MAS NMR spectra and infrared and Raman spectroscopy is presented.

The commercial significance of some of the complexes formed in group 11 metal cyanide systems has attracted keen interest in the study of this group of cyanides. Details of the solid-state structures of the group 11 metal cyanides MCN (where M = Cu, Ag and Au) remain unknown, however. A study was therefore conducted using X-ray and neutron powder diffraction techniques and vibrational spectroscopy to acquire a more detailed insight into the structures of these complexes.

A study was conducted on the Fourier transform (FT)-infrared and polarized FT-Raman spectra of pure and diluted titanium tetraisopropoxide (TPT) and of 2-propanol to identify a comprehensive assignment of their vibrational spectra. Highly polarized band in the Raman spectrum were attributed to symmetrically coupled ligand modes while antisymmetrically coupled ligand modes were found to cause strong bands in the infrared spectrum. Band shifts and splittings in the TPT infrared spectrum found to result from the lifting of the degeneracy of strong ligand modes by molecular association.

Results of the solid-state 199Hg MAS NMR studies of (Hg(SCN)2), (Hg(SeCN)2), M(Hg(SCN)3), M2(Hg(SCN)4) are described. The crystal structure of (Hg(SeCN)2) was determined to help in the interpretation of the NMR information. Spinning sideband analysis was used in the determination of the 199Hg shielding anisotropy and asymmetry parameters delta-sigma and eta from the solid-state 199Hg MAS NMR spectra. Effects of changes in the mercury coordination number and of distortion of the coordination environment on the shielding parameters were also interpreted.

The complex (Cu4(tu)7)(SO4)2*H2O was isolated through the addition of thiourea to a copper(II) sulfate electrolyte solution composed of 2 M H2SO4 and 0.7 M CuSO4. Findings indicated that the copper atoms are tetrahedrally arranged in which one of the copper atoms is four-coordinate, while the other three have trigonal planar coordination with Cu***Cu distances of 2.899(2)-2.967(2) angstroms. The copper-thiourea clusters are interlinked by sulfate ions, which strongly interact with the thiourea ligands through hydrogen bonds.

The use of electrospray mass spectrometry was demonstrated for the study of metal thiolate complexes and metal chalcogenide thiolate clusters. The exchanges of M, E and X that transpired in various mixtures of thiophenolate clusters of CdS, SdSe, and ZnS and of cadmium and zinc thiophenolate complexes were studied. The measurements made yielded relative stability data. The ions containing zinc as the metal exhibited lower resistance to fragmentation compared with the cadmium analogues.

Electronic structure calculations have been used on (PR3MCl) (M=Ag,Au;R=H,Me) and ((PR3)2M)+ to study the contractions of relativist bond lengths. The study also examined the relative M-P bond strengths and lengths in gold compounds with PMe3 and PH3 ligands. These ligands form part of many different types of gold compounds. The results of the study back the notion of longer and stronger bonds which have been suggested after studies of phosphine ligands and transition metal complexes.

The reaction between tris(2,4,6-trimethoxyphenyl)phosphine (TMPP) and Cu(I) iodide in acetonitrile yields 1:1 complexes. The mole ratio of the reactants influences the structures of the complexes. Room-temperature single-crystal X-ray studies help analyze the structure of the 1:1 molecular adduct ((TMPP)CuI) from a reaction between TMPP and CuI in a 1:2 ratio. The complex has mononuclear ((TMPP)CuI) molecules that have linear two-coordination about the copper atom. 31 P NMR and IR studies reveal the formation of a different 1:1 complex by a reaction between TMPP and CuI in a 1:1 ratio.

The synthesis of (tris(2,4,6-trimethoxyphenyl)phosphine)AgX, where X = Cl, Br and I, by the reaction of the phosphine ligand with AgX was undertaken. (TMPP)AgCl and (TMPP)AgBr were found to be isomorphous with each other, were monomeric, and possessed a silver atom residing in an almost linear two-coordinate environment. Both complexes also contained the P-Ag-X fragment. Moreover, the far-infrared spectra of the complexes showed strong bands at 282 cm(super -1) for (TMPP)AgCl and 215 cm(super -1) for (TMPP)AgBr.