ISSN:
1089-7690
Source:
AIP Digital Archive
Topics:
Physics
,
Chemistry and Pharmacology
Notes:
We present the photoelectron spectra of Cl−, Br−, and I− solvated in acetonitrile clusters (CH3CN)n with n=1–33, 1–40, and 1–55, respectively, taken with 7.9 eV photon energy. Anion–solvent electrostatic stabilization energies are extracted from the measured vertical electron binding energies. The leveling of stabilization energies beyond n=10–12 for the three halides signifies the completion of the first solvation layer. This is different from the behavior of anion–water clusters which probably do not fill the first solvation layer, but rather form surface solvation states. Classical molecular dynamics simulations of halide–acetonitrile clusters reproduce the measured stabilization energies and generate full solvation shells of 11–12, 12, and 12–13 solvent molecules for Cl−, Br−, and I−, respectively. Ordered shell structures with high stability were found for the clusters of Cl−, Br−, and I− with n=9, 9, and 12. This special stability is reflected in the intensity distribution of the clusters in the mass spectra. Larger anion–acetonitrile clusters have the molecules beyond the first solvation layer packed in a small droplet which is attached to the first layer. It is suggested that in general, anions solvated in large clusters of polar solvents, might be located close to their surface. © 1996 American Institute of Physics.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1063/1.472131
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