Mimicking solvent shells in the gas phase. II. Solvation of K+.
J Chem Phys
; 124(2): 024319, 2006 Jan 14.
Article
in En
| MEDLINE
| ID: mdl-16422595
ABSTRACT
The observed gas-phase coordination number of K+ in K+(H2O)m clusters is smaller than that observed in bulk solution, where the coordination number has been reported to be between 6 and 8. Both theoretical and gas-phase studies of K+(H2O)m cluster ions point to a coordination number closer to 4. In the gas phase, the coordination number is determined by a variety of factors-the most critical being the magnitude of the K+...ligand pairwise interaction. Decreasing the magnitude of the ion...ligand interaction allows more ligands to directly interact with the cation. One method for decreasing the ion...ligand interaction in K+(H2O)m clusters is to systematically substitute weakly bound ligands for the more strongly bound water molecules. The systematic introduction of para-difluorobenzene (DFB) to K+(H2O)m clusters was monitored using infrared photodissociation spectroscopy in the OH stretching region. By varying the ratio of DFB molecules to water molecules present in K+(H2O)m(DFB)n clusters, the observed coordination number of gas-phase K+ was increased to 8, similar to that reported for bulk solution.
Search on Google
Database:
MEDLINE
Language:
En
Journal:
J Chem Phys
Year:
2006
Type:
Article
Affiliation country:
United States