Clustering of metal atoms in organic media. II. Effect of support on nickel catalysts prepared by solvated metal atom dispersion (SMAD)

1982 ◽  
Vol 47 (5) ◽  
pp. 843-848 ◽  
Author(s):  
Kiyotaka Matsuo ◽  
Kenneth J. Klabunde
Keyword(s):  
Metal Atom ◽  
Nickel Catalysts ◽  
Organic Media ◽  
Metal Atoms ◽  
Effect Of Support ◽  
Solvated Metal Atom Dispersion

Hexaruthenium and octaruthenium carbonyl cluster complexes derived from 2-amino-6-methylpyridine — Novel coordination modes for 2-imidopyridines

2006 ◽  
Vol 84 (2) ◽  
pp. 105-110 ◽  
Author(s):  
Javier A Cabeza ◽  
Ignacio del Río ◽  
Pablo García-Álvarez ◽  
Daniel Miguel
Keyword(s):  
Metal Atom ◽  
Cluster Compounds ◽  
Carbonyl Cluster ◽  
Amido Ligands ◽  
Ruthenium Cluster ◽  
Coordination Type ◽  
Metal Atoms ◽  
Pyridine Nitrogen ◽  
Cluster 2 ◽  
Reflux Temperature

The hexanuclear ruthenium cluster [Ru6(µ3-H)2(µ-H)2(µ4-κ2-ampy)2(CO)14] (1) and the octanuclear one [Ru8(µ-H)(µ4-κ2-ampy)3(µ3-κ2-Hampy)(µ-CO)2(CO)15] (2) have been prepared by treating [Ru6(µ3-H)2(µ5-κ2-ampy)(µ-CO)2(CO)14] with 2-amino-6-methylpyridine (H2ampy) in decane at reflux temperature. Their metal atoms are supported by ligands that derive from the activation of one (complex 2) or both N—H bonds (complexes 1 and 2) of the H2ampy amino fragment. Both contain at least one ampy ligand featuring an unprecedented coordination type: the imido N atom caps a triangle of metal atoms while the pyridine nitrogen is attached to an additional metal atom. One of the ampy ligands of cluster 2 also displays another unprecedented coordination type: it caps a distorted square of metal atoms through the imido N atom while the pyridine nitrogen is attached to one of the atoms included in that square.Key words: ruthenium, cluster compounds, amido ligands, imido ligands.

Pd1/BN as a promising single atom catalyst of CO oxidation: a dispersion-corrected density functional theory study

RSC Advances ◽  
2015 ◽  
Vol 5 (103) ◽  
pp. 84381-84388 ◽  
Author(s):  
Zhansheng Lu ◽  
Peng Lv ◽  
Jie Xue ◽  
Huanhuan Wang ◽  
Yizhe Wang ◽  
...  
Keyword(s):  
Density Functional Theory ◽  
Co Oxidation ◽  
Metal Atom ◽  
Density Functional ◽  
Single Atom ◽  
Two Dimensional ◽  
Density Functional Theory Study ◽  
Functional Theory ◽  
Metal Atoms ◽  
Two Dimensional Materials

Single metal atom catalysts exhibit extraordinary activity in a large number of reactions, and some two-dimensional materials (such as graphene and h-BN) are found to be prominent supports to stabilize single metal atoms.

AP-FIM INVESTIGATION OF THE INITIAL STAGE OF OXIDATION ON THE SURFACE OF ALLOYS

1995 ◽  
Vol 02 (02) ◽  
pp. 177-181 ◽  
Author(s):  
D.G. REN
Keyword(s):  
Binding Energy ◽  
Field Strength ◽  
Metal Atom ◽  
Exposure Period ◽  
Atom Probe ◽  
Field Evaporation ◽  
Residual Oxygen ◽  
Metal Atoms ◽  
Initial Stage ◽  
The Difference

This paper reports a study of the initial stage of oxidation on the surface of alloys by field-ion microscopy and atom probe (AP-FIM). The samples used in this investigation contained Ni, Ni-Cr, Ni-Al, Ti-Al , and Pt-Rh metals and alloys. A clean-tip surface, after atom-probe analysis, was exposed in the atmosphere of residual oxygen (vacuum 10−4 torr) for a few hours. AP analysis found that a small quantity of oxygen was adsorbed on the surface of the alloys. The clusters of a combination of a metal atom with an oxygen, i.e., PtO +2, NiO +2, and TiO +2 were determined by AP. The experiment found that the binding energy between metal atom on the surface of alloys was reduced when oxygen was adsorbed on the surface. The binding energy of surface atoms was determined according to the field strength of the tip surface. The reduction of the binding energy was about 0.5–2.0 eV, which changed following the exposure period in the atmosphere and depending on the kind of alloys used. The difference in field-ion image due to adsorption of oxygen was observed as compared to without the oxygen. The results of the experiment show that oxygen was absorbed on the “clean surface” of alloys. First the oxygen molecule was dissociated to oxygen atoms by the reaction with metal atoms and then formed the metal-oxygen bonding (M+O→MO) . This is an initial stage of oxidation on the surface of alloys. The clusters of combining oxygen did not dissociate during the field-evaporation process with 4.5 V/Å field strength.

scholarly journals catena-Poly[[[2-({6-[(pyrimidin-2-ylsulfanyl-κS)methyl]pyridin-2-yl-κN}methylsulfanyl)pyrimidine]copper(I)]-μ-thiocyanato-κ2N:S]

2012 ◽  
Vol 68 (4) ◽  
pp. m429-m429
Author(s):  
Rong Peng ◽  
Seik Weng Ng
Keyword(s):  
Metal Atom ◽  
Title Compound ◽  
Donor Site ◽  
Helical Chain ◽  
Thiocyanate Ion ◽  
Heterocyclic Ligand ◽  
Metal Atoms

TheN-heterocyclic ligand in the title compound, [Cu(NCS)(C15H13N5S2)]n, coordinates to the CuIatom through its pyridine N-donor site, and adjacent metal atoms are bridged by the thiocyanate ion, forming a helical chain along thebaxis. The geometry of the metal atom is tetrahedral owing to a somewhat long intramolecular Cu—S interaction of 2.5621 (9) Å.

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