Abstract
Helium atoms bind strongly to alkali cations which, when embedded in liquid helium, form so‐called snowballs. Calculations suggest that helium atoms in the first solvation layer of these snowballs form rigid structures and that their number (n) is well defined, especially for the lighter alkalis. However, experiments have so far failed to accurately determine values of n. We present high‐resolution mass spectra of Na+Hen, K+Hen, Na2+Hen and K2+Hen, formed by electron ionization of doped helium droplets; the data allow for a critical comparison with several theoretical studies. For sodium and potassium monomers the spectra indicate that the value of n is slightly smaller than calculated. Na2+Hen displays two distinct anomalies at n=2 and n=6, in agreement with theory; dissociation energies derived from experiment closely track theoretical values. K2+Hen distributions are fairly featureless, which also agrees with predictions.
Department
Physics
Publication Date
2-28-2012
Journal Title
Chemistry—A European Journal
Publisher
Wiley
Digital Object Identifier (DOI)
Document Type
Article
Recommended Citation
L. An der Lan, P. Bartl, C. Leidlmair, R. Jochum, S. Denifl, O. Echt, and P. Scheier, Solvation of Na+, K+ and their dimers in helium, Chem. Eur. J. 18 (2012) 4411-4418, DOI 10.1002/chem.201103432, April 2012
Rights
Copyright © 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim
Comments
This is an article published by Wiley in Chemistry—A European Journal in 2012, available online: https://dx.doi.org/10.1002/chem.201103432