Density Functional Calculations of Metal Clusters: Structure, Dynamics, and Reactivity - Metallic Systems: A Quantum Chemist's Perspective - page 306

Cation Neutral

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FIGURE 9.16 Schematic. molecular. orbital. correlation. diagram. from. the. cationic. to. the.
neutral.ground-state.trimers..The.adding.of.the.extra.electron.is.indicated.by.a.dotted.arrow..
(Reprinted.from.Lopez.Arvizu,.G..et.al.,. J. Chem. Phys .,.126(19),.May.21,.194102-1,.2007..
With.permission.)

the. ground-state. structure. of. small. anionic. nickel. clusters,. experiments. based. on.
negative-ion.vibrationally.resolved.spectroscopy.would.be.highly.desirable.

9.3.2 m etal c luSter o xideS (v 3 o, n B 3 o)
The.gas-phase.spectroscopic.study.of.TM.oxides.is.of.experimental.and.theoretical.
interest.. Experimentally,. properties. related. to. the. metal-oxygen. bond. are. crucial.
for.understanding.chemisorption.and.catalytic.activities.of.metal.oxides..In.particu-
lar,.vanadium.oxides.are.important.in.catalysis,.and.the.investigation.of.vanadium-.
oxygen. chemical. bonding. is. of. great. interest.. Theoretically,. molecules. containing.
TMs. are. rather. challenging. due. to. the. open. d . shells.. Simple. TM. oxide. molecules.
provide.ideal.systems.for.the.investigation.of.the.reliability.of.theoretical.methods..
The.study.of.TM.oxide.species.in.the.gas.phase.by.photoelectron.spectroscopy.offers.
a. unique. opportunity. to. probe. the. electronic. structure. of. the. isolated. molecules..
Dyke.et.al..reported.the.irst.photoelectron.spectroscopy.experiment.of.neutral.VO.
[182].. Negative. ion. photoelectron. spectroscopy. was. applied. to. the. group. 5. metal.
trimer.monoxides.V 3 O,.Nb 3 O,.and.Ta 3 O,.yielding.insight.into.the.bonding.of.these.
early.TM.cluster.oxides.[128]..The.experimental.data.reported.in.this.work.provide.
a. benchmark. for. computational. studies. of. partially. ligated. early. TM. clusters.. In.
particular,. the. vibrationally. resolved. 488.nm. negative. ion. photoelectron. spectrum.
of.V 3 O.provides.measurements.of.its.electron.afinity.and.vibrational.frequencies,.
which.can.be.summarized.as.follows..The.electron.afinity.of.V 3 O.is.1.218.±.0.008.eV.