Spectroscopic and Theoretical Characterization of Structure

In recent years researchers have begun to use density functional theory to model supported metal complexes, representing the support as a cluster (fragment of the bulk support). Examples of supported complexes characterized by both theory and spectroscopy are presented below. 

When samples incorporate uniform mononuclear metal complexes, then EXAFS data may provide high-quality information about the interactions between the metal and oxygen atoms of the support. Evidence of the metal-support interface has also been determined by theory and, indirectly, by IR spectra indicating the symmetry and thus the number of atoms of the support that act as ligands bonded to the metal. 

Rhodium carbonyls on oxide and zeolite supports have been investigated extensively and are some of the best-understood supported metal 

Miessner (1994) showed that partial decarbonylation of this supported complex by treatment in H2 at temperatures of 200 to 250°C leads to complexes that are so highly reactive that they combine with N2 to give well-defined supported complexes with dinitrogen ligands. This remarkable reactivity suggests possibilities for new catalytic properties of these and related supported metal complexes. 

Comparison of Structural Parameters Determined by Density Functional Theory and by EXAFS Spectroscopy Characterizing Samples Made from Chemisorption of [Rh(CO)2(acac)] on Dealuminated Y Zeolite (Goellner, Gates et al., 2000)  

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