Density Functional Calculations of Metal Clusters: Structure, Dynamics, and Reactivity - Metallic Systems: A Quantum Chemist's Perspective - page 305

Neutral

M = 7

M = 3 M = 5

(2.360)
[2.320]

(2.340)
[2.306]

M = 3

(2.283)
[2.230]

(2.187)
[2.148]

(2.317)
[2.279]

(2.187)
[2.148]

(2.250)
[2.222]

Cationic

M = 6

(2.370)
[2.330]

M = 4

M = 4

M = 4

(2.340)
[2.302]

(2.287)
[2.246]

(2.332)
[2.294]

(2.304)
[2.265]

Anionic

M = 4 M = 4

(2.242)
[2.248]

(2.245)
[2.246]

(2.245)
[2.246]

M = 6 M = 8

(2.287)
[2.246]

(2.432)
[2.390]

(2.287)
[2.246]

(2.297)
[2.261]

FIGURE 9.15 Ground-state.structures,.bond.lengths.(in.Å),.and.multiplicities.of.Ni n ,. Ni n + , .
and. Ni n − . ( n .=.2-5). clusters.. The. newly. developed. DZVP-GGA,. parentheses,. and. TZVP-
GGA,.square.brackets,.basis.sets.in.combination.with.the.PW86.functional.were.employed..
(Reprinted.from.Lopez.Arvizu,.G..et.al.,. J. Chem. Phys .,.126(19),.May.21,.194102-1,.2007..
With.permission.)

TZVP-GGA/PW86.methods,.this.result.is.inverted.and.the.pyramidal.structure.on.
the.septet.PES.is.the.favored.one.(Figure.9.15)..The.energy.difference.between.these.
two.structures.is.0.16.eV.with.the.DZVP-GGA/PW86.method.and.0.22.eV.with.the.
TZVP-GGA/PW86.calculation,.respectively.
For. these. nickel. clusters,. adiabatic. ionization. potentials. and. adiabatic. electron.
afinities.were.also.presented.(Tables.II.and.IV.of.Ref..[146])..The.results.were.com-
pared.with.the.experimental.data.available.in.the.literature..The.trends.observed.in.
the.energetic.properties.showed.agreement.with.the.ones.determined.experimentally,.
demonstrating.that.the.structural.assignment.of.the.clusters.can.be.performed.with.
good.resolution.over.the.ionization.potential.[146]..For.unequivocal.assignment.of.