Structural characterization of the anions [Rh6(CO)15X]− [X = COEt and CO(OMe)]

The anions [Rh₆(CO)₁₅X]^?, with X = COEt and CO(OMe), have been studied by single-crystal X-ray diffraction. They contain octahedral rhodium clusters, with mean metalmetal distances of 2.779 and 2.765 », respectively. The carbonyl stereochemistry in the two anions is similar to that of Rh₆(CO)₁₆, with one terminal CO group replaced by the X ligand. The RhC(carbomethoxy) bond distance (1.96(2) ») is significantly shorter than the RhC(acyl) distance (2.06(2) »).     

Three novel interpenetrating diamondoid networks from self-assembly of 1,12-dodecanedinitrile with silver(I) salts

The self-assembly of 1,12-dodecanedinitrile (ddn) with various silver salts (NO(3)(-), PF(6)(-), AsF(6)(-), ClO(4)(-)) afforded new polymeric coordination networks with the general formula [Ag(ddn)(2)]X. All these species contain interpenetrating diamondoid nets showing interesting features: with X=NO(3)(-) the cationic [Ag(ddn)(2)](+) network exhibits the highest interpenetration (tenfold) ever found within diamondoid nets exclusively based on coordinative bonds. When X=PF(6)(-) or AsF(6)(-) an eightfold diamondoid network is obtained that shows an unusual [4+4] mode of interpenetration, instead of the "normal" set of eight nets equally translated along a principal axis of the adamantanoid cages. The polymeric species that forms with X=ClO(4)(-) is a fourfold interpenetrating diamondoid network; the lower degree of interpenetration in this case is related to the conformation assumed by the flexible ddn ligands.     

Binding of single gold atoms on thin MgO(001) films

In the present Letter the first electron paramagnetic resonance spectra of single metal atoms on a single crystalline oxide surface are presented. For Au atoms on a MgO(001) film investigated here an analysis of the angular dependent resonance positions and the hyperfine coupling to (17)O shows that the atoms are bound on top of oxygen ions on the terrace of the film. This result is in perfect agreement with scanning tunneling microscopy measurements at 5 K presented here. The measured hyperfine matrix components allow an experimental verification of the theoretically proposed binding mechanism of Au atoms on MgO. In particular, the large reduction of the isotropic hyperfine coupling constant of supported Au as compared to free atoms is not due to a charge transfer at the interface but a hybridization of orbitals and a resulting polarization of the unpaired electron.     

ChemInform Abstract: Ab initio Theory of Point Defects in Oxide Materials: Structure,Properties, Chemical Reactivity

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.     

ChemInform Abstract: A Route Toward the Generation of Thermally Stable Au Cluster Anions Supported on the MgO Surface.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.