title: The structure of the hydrogen ion (H(aq)+) in water.
abstract: The hydrogen ion in water, H(aq)(+), is a unique H(13)O(6)(+) entity that defines the boundary of positive-charge delocalization. Its central unit is neither a C(3v) H(3)O(+) Eigen-type ion nor a typical H(5)O(2)(+) Zundel-type ion. IR spectroscopy indicates that the H(13)O(6)(+) ion has an unexpectedly long central O...O separation (>>2.43 A), showing that in comparison with the gas and solid phases, the environment of liquid water is uniquely proficient in delocalizing positive charge. These results will change the description of H(aq)(+) in textbooks of chemistry, and a more extensive delocalization of positive charge may need to be incorporated into descriptions of mechanisms of aqueous proton transport.
authors.affiliation: Department of Chemistry, University of California, Riverside, California 92521-0403, USA.
authors.forename: Evgenii S
authors.initials: ES
authors.lastname: Stoyanov
authors.forename: Irina V
authors.initials: IV
authors.lastname: Stoyanova
authors.forename: Christopher A
authors.initials: CA
authors.lastname: Reed
mesh_terms: D015394:Molecular Structure; D011522:Protons; D013055:Spectrophotometry, Infrared; D014867:Water / Q000737:chemistry*
chemical_list: D011522:Protons; D014867:Water