Interaction between liquid water and hydroxide revealed by core-hole de-excitation

Emad F. Aziz, Niklas Ottosson, Manfred Faubel, Ingolf V. Hertel, Bernd Winter

Research output: Contribution to journalArticlepeer-review

175 Scopus citations

Abstract

The hydroxide ion plays an important role in many chemical and biochemical processes in aqueous solution. But our molecular-level understanding of its unusual and fast transport in water, and of the solvation patterns that allow fast transport, is far from complete. One proposal seeks to explain the properties and behaviour of the hydroxide ion by essentially regarding it as a water molecule that is missing a proton, and by inferring transport mechanisms and hydration structures from those of the excess proton. A competing proposal invokes instead unique and interchanging hydroxide hydration complexes, particularly the hypercoordinated OH-(H2O)4 species and tri-coordinated OH-(H2O)3 that can form a transient hydrogen bond between the H atom of the OH- and a neighbouring water molecule. Here we report measurements of core-level photoelectron emission and intermolecular Coulombic decay for an aqueous hydroxide solution, which show that the hydrated hydroxide ion is capable of transiently donating a hydrogen bond to surrounding water molecules. In agreement with recent experimental studies of hydroxide solutions, our finding thus supports the notion that the hydration structure of the hydroxide ion cannot be inferred from that of the hydrated excess proton.

Original languageEnglish
Pages (from-to)89-91
Number of pages3
JournalNature
Volume455
Issue number7209
DOIs
StatePublished - 4 Sep 2008
Externally publishedYes

Fingerprint

Dive into the research topics of 'Interaction between liquid water and hydroxide revealed by core-hole de-excitation'. Together they form a unique fingerprint.

Cite this