jz500693k_si_liveslides.zip (5.15 MB)
Evolution of Hydrogen-Bond Networks in Protonated Water Clusters H+(H2O)n (n = 1 to 120) Studied by Cryogenic Ion Mobility-Mass Spectrometry
media
posted on 2015-12-24, 16:15 authored by Kelly
A. Servage, Joshua A. Silveira, Kyle L. Fort, David H. RussellCryogenic (80 K) ion mobility-mass spectrometry (cryo-IM-MS) is
employed to study structural transitions of protonated water clusters
in both the small, H+(H2O)n (n = 1 to 30), and large, (n = 31 to ∼120), size regions. In agreement with previous studies,
we find compelling evidence of regions of uniform cluster decay in
the small size region, accompanied by sharp transition points whereby
the loss of a single water monomer induces a different H-bonding motif.
The investigation of the isomeric distribution of each species at
80 K reveals experimental evidence supporting the notion that H+(H2O)n (n = 6) is the smallest system to possess both Eigen- (H3O+) and Zundel- (H5O2+) centered structures. Cryo-IM-MS is particularly well-suited for
studying clusters in the large size region, for which previous spectroscopic
experimental studies are scarce.