Chemistry Reference
In-Depth Information
Fig. 6 IR-MPD spectrum for Au
7
Kr (
bottom panel
), finite temperature IR spectra from molecular
dynamics simulations at 100 K (2nd from
bottom
;
red trace
,Au
7
Kr;
dashed black
,Au
7
) and
harmonic IR spectra for the given limiting structures (
remaining panels
). At 100 K the Kr is not
bound to a specific Au atom, but preferentially localised above and below the Au
7
plane (
green
:
80 % isosurface). From [
60
]
The good agreement between the experimental IR-MPD spectra of Au
19
Kr and
Au
20
Kr and the harmonic vibrational spectra of the bare clusters allows for the
conclusion that in these cases (i) the messenger is not significantly perturbing the
vibrational properties of the gold clusters and (ii) the vibrations are largely har-
monic. This may not be generally true and, particularly for small clusters, larger
deviations between the spectra and the predictions can be found.
The influence of Kr binding on the predicted harmonic IR spectra of Au
7
is
illustrated in the upper panels of Fig.
6
. Upon binding Kr, the relative intensities of
