Chemical reactivity on gas-phase metal clusters driven by blackbody infrared radiation.

We report the observation of chemical reactions in gas-phase Rh(n)(N2O)m(+) complexes driven by absorption of blackbody radiation. The experiments are performed under collision-free conditions in a Fourier transform ion cyclotron resonance mass spectrometer. Mid-infrared absorption by the molecularly adsorbed N2O moieties promotes a small fraction of the cluster distribution sufficiently to drive the N2O decomposition reaction, leading to the production of cluster oxides and the release of molecular nitrogen.

Collisional activation of N2O decomposition and CO oxidation reactions on isolated rhodium clusters.

The reactions of nitrous oxide decorated rhodium clusters, RhnN2O(+) (n = 5, 6), have been studied by Fourier transform ion cyclotron resonance mass spectrometry. Collision induced dissociation with Ar is shown to lead to one of two processes; desorption of the intact N2O moiety (indicating molecular adsorption in the parent cluster) or N2O decomposition liberating molecular nitrogen with the latter becoming increasingly dominant at higher collision energies. Consistent with the results of earlier studies, which employed infrared excitation [Hermes, A.

Infrared driven CO oxidation reactions on isolated platinum cluster oxides, Pt(n)O(m)+.

This collaboration has recently shown that infrared excitation can drive decomposition reactions of molecules on the surface of gas-phase transition metal clusters. We describe here a significant extension of this work to the study of bimolecular reactions initiated in a similar manner. Specifically, we have observed the infrared activated CO oxidation reaction (CO(ads) + O(ads) --> CO2(g)) on isolated platinum oxide cations, Pt(n)O(m)+.

Infrared-induced reactivity of N2O on small gas-phase rhodium clusters.

Far- and mid-infrared multiple photon dissociation spectroscopy has been employed to study both the structure and surface reactivity of isolated cationic rhodium clusters with surface-adsorbed nitrous oxide, Rh(n)N(2)O(+) (n = 4-8). Comparison of experimental spectra recorded using the argon atom tagging method with those calculated using density functional theory (DFT) reveals that the nitrous oxide is molecularly bound on the rhodium cluster via the terminal N-atom. Binding is thought to occur exclusively on atop sites with the rhodium clusters adopting close-packed structures.

Infrared induced reactivity on the surface of isolated size-selected clusters: dissociation of N2O on rhodium clusters.

Multiple photon infrared excitation of size-selected Rh(6)N(2)O(+) clusters drives surface chemistry resulting in partially oxidized clusters.

The electronic spectrum of vanadium monoxide across the visible: new bands and new insight.

Resonance enhanced multiphoton ionization spectra of vanadium monoxide (VO) have been measured in the 16,000-23,300 cm(-1) region. A series of intense peaks, identified as the VO C (4)Sigma(-) (v('))-X (4)Sigma(-) (v(")=0) progression, has been recorded up to v(')=7 and vibrational and rotational parameters have been extracted by simulation of the rotationally resolved spectra. Additional weak transitions in the spectrum are assigned to the 2 (2)Pi-X (4)Sigma(-) spin-forbidden band system allowing the first direct determination of a spin-orbit coupling constant within the doublet spin manifold of VO.