https://doi.org/10.1140/epjd/e2003-00105-x
Vibrational spectroscopy of large water clusters of known size
Max–Planck–Institut für Strömungsforschung, 37073 Göttingen, Germany
Corresponding author: a ubuck@gwdg.de
Received:
10
September
2002
Published online:
3
July
2003
The structure of large water clusters of known size distributions
is investigated by vibrational
spectroscopy of the OH stretch mode.
The water clusters are predissociated by a pulsed tunable infrared
optical parametrical oscillator (OPO) in the frequency range
cm-1.
Their fragments are detected off-axis
by electron impact ionization and
mass analyzed by a quadrupole mass spectrometer. The largest ion signal
stems from the neutral water hexamer fragment. The ion yield
is investigated at certain wavelengths while the size of the clusters is varied,
and for certain sizes complete absorption spectra of the OH stretch
motion are measured.
Fingerprints of the different coordination types of the water molecules
in the clusters are found and it turns out that our method is especially
sensitive to amorphous structures with frequencies shifting
in the range of 
cm-1.
PACS: 36.40.Mr – Spectroscopy and geometrical structure of clusters / 61.46.+w – Nanoscale materials: clusters, nanoparticles, nanotubes, and nanocrystals
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 2003
