Nickel, clusters

Figure Cl.1.5. Nickel cluster magnetic moment per atom (p) as a function of cluster size, at temperatures between 73 and 198 K. Apsel S E, Emmert J W, Deng J and Bloomfield L A 1996 Phys. Rev. Lett. 76 1441, figure 1.

Parks E K, Winter B J, Klots T D and Riley S J 1992 Evidence for polyicosahedral structure in ammoniated iron, cobalt and nickel clusters J. Chem. Rhys. 96 8267... 

Nayak S K, Khanna S N, Rao B K and Jena P 1997 Physics of nickel clusters energetics and equilibrium geometries J. Phys. Chem. A 101 1072... 

Billas I M L, Chatelain A and de Heer W A 1994 Magnetism from the atom to the bulk in iron, cobalt, and nickel clusters Science 265 1682... 

I. M. L. BiUas, A. Chatelain and W. A. de Heer, Magnetism from the atom to the brdk in iron, cobalt and nickel clusters . Science 265.T682 (1994). 

M. Tomonari, H. Tatewaki and T. Nakamura, The electronic structure of small nickel clusters , J. Chem. Phys. 85 2875 (1986). 

This paper describes the successful incorporation of molybdenum and molybdenum-nickel clusters into zeolites with 12-membered ring by aqueous ion exchange and application of the resulting materials to HDS reaction of benzothiophene. Stoichiometry of the ion exchange was examined by elemental analysis. UV-visible spectroscopy and EXAFS measurements were carried out to investigate the structure of molybdenum species loaded on zeolites. 

Table 5 shows HDS product distributions over several catalysts prepared by using the molybdenum-nickel cluster 2. Sulfur content in decane was adjusted to 5.0 wt% in these experiments. MoNi/NaY was found to be more active than MoNi/Al203. It is to be noted that during the high temperature pretreatment the original cluster structure would have been changed. However, the high activity of the MoNi/NaY catalyst for benzothiophene HDS is probably due to the formation of active sites derived from this particular mixed metal cluster. 

Kruger, S., Stener, M. and Rosch, N. (2001) Relativistic density functional study of gold coated magnetic nickel clusters. Journal of Chemical Physics, 114, 5207-5215. 

Knickelhein MB, Yang S, Riley SJ. 1990. Near-threshold photoionization of nickel clusters Ionization potentials for Nis to Nipo. J Chem Phys 93 94-104. 

The use of the nickel cluster [Ni4(CNCMe3)7] in hydrogenation of alkynes was recently described (222, 223). 

Homogeneous catalysts have now been reported for hydrogenation of carbon monoxide, a combustion product of coal (see Section VI,B). More effective catalysts will undoubtedly be discovered in the near future. Polynuclear or, at least, binuclear sites are favored for reduction of the triple bond in carbon monoxide (see Section VI,B), and this together with the popular parallelism to heterogeneous systems, has renewed interest in metal clusters as catalysts (see Section VI). A nickel cluster is the first catalyst reported for mild (and selective) hydrogenation of the triple bond in isocyanide (see Section VI,A). The use of carbon monoxide and water as an alternative hydrogen source is reattracting interest (see Section VI,C). 

MEASUREMENT AND INTERPRETATION OF THE MAGNETIC MOMENTS OF NICKEL CLUSTERS... 

Density Functional Calculations for Small Nickel Clusters... 

Magnetism from the Atom to the Bulk in Iron, Cobalt and Nickel Clusters. 

Physics of Nickel Clusters. 2. Electronic Structure and Magnetic Properties. 

Washington, J. and Kubiak, C.P. (1998) Infrared spectroelectrochemical and electrochemical kinetics studies of the reaction of nickel cluster radicals [Ni3(p2-dppm)3(P3-L)(P3-I)] (L = CNR,... 

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