Exafs Studies of Oxide Supported Osmium Carbonyl Clusters
نویسندگان
چکیده
The reactions of triosmium carbonyl clusters on functionalised high surface area silicas have been monitored by 0s L(II1) edge EXAFS. Interaction of [OS~(CO)~~] with HS(CH2)jSIL affords HOS~(CO)~~[S(CH~)~SIL], which was structurally characterised using spherical wave methods to analyse the EXAFS data. Subsequent thermolysis in vacuo yields a new material. Coordination to " ~ 2 CO groups, 0 oxygen atoms, %1 sulphur and %2 osmium atoms is evident; a trinuclear structure is consistent with these coordination numbers. The initial product of the interaction of [H20s3(C0)101 with phosphinated silica is a phosphine adduct of this cluster. Subsequent thermolysis yields a partially decarbonylated species similar to that formed on the thiolated silica with the exception of the absence of coordination to the original anchoring ligand. Coordination to surface oxygen accompanies thermal decarbonylation.
منابع مشابه
An EXAFS study of the formation of small metal aggregates on MgO using organometallic compounds as precursors
EXAFS measurements have been carried out on very small osmium and rhenium metal particles supported on MgO. The metal particles were formed via decornposition and subsequent reduction in hydrogen of metal carbonyl clusters.
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