The nature and transport mechanism of hydrated hydroxide ions in aqueous solution

Mark Tuckerman, Dominik Marx, Michele Parrinello

Research output: Contribution to journalArticle

Abstract

Compared to other ions, protons (H+) and hydroxide ions (OH-) exhibit anomalously high mobilities in aqueous solutions. On a qualitative level, this behaviour has long been explained by 'structural diffusion' - the continuous interconversion between hydration complexes driven by fluctuations in the solvation shell of the hydrated ions. Detailed investigations have led to a clear understanding of the proton transport mechanism at the molecular level2-8. In contrast, hydroxide ion mobility in basic solutions has received far less attention2,3,9,10, even though bases and base catalysis play important roles in many organic and biochemical reactions and in the chemical industry. The reason for this may be attributed to the century-old notion11 that a hydrated OH- can be regarded as a water molecule missing a proton, and that the transport mechanism of such a 'proton hole' can be inferred from that of an excess proton by simply reversing hydrogen bond polarities11-18. However, recent studies2,3 have identified OH- hydration complexes that bear little structural similarity to proton hydration complexes. Here we report the solution structures and transport mechanisms of hydrated hydroxide, which we obtained from first-principles computer simulations that explicitly treat quantum and thermal fluctuations of all nuclei19-21. We find that the transport mechanism, which differs significantly from the proton hole picture, involves an interplay between the previously identified hydration complexes2,3 and is strongly influenced by nuclear quantum effects.

Original languageEnglish (US)
Pages (from-to)925-929
Number of pages5
JournalNature
Volume417
Issue number6892
DOIs
StatePublished - Jun 27 2002

Fingerprint

Protons
Ions
Chemical Industry
hydroxide ion
Catalysis
Computer Simulation
Hydrogen
Hot Temperature
Water

ASJC Scopus subject areas

  • General

Cite this

The nature and transport mechanism of hydrated hydroxide ions in aqueous solution. / Tuckerman, Mark; Marx, Dominik; Parrinello, Michele.

In: Nature, Vol. 417, No. 6892, 27.06.2002, p. 925-929.

Research output: Contribution to journalArticle

Tuckerman, Mark ; Marx, Dominik ; Parrinello, Michele. / The nature and transport mechanism of hydrated hydroxide ions in aqueous solution. In: Nature. 2002 ; Vol. 417, No. 6892. pp. 925-929.
@article{bf8a56d79c144601a5eefbafa16ba4dd,
title = "The nature and transport mechanism of hydrated hydroxide ions in aqueous solution",
abstract = "Compared to other ions, protons (H+) and hydroxide ions (OH-) exhibit anomalously high mobilities in aqueous solutions. On a qualitative level, this behaviour has long been explained by 'structural diffusion' - the continuous interconversion between hydration complexes driven by fluctuations in the solvation shell of the hydrated ions. Detailed investigations have led to a clear understanding of the proton transport mechanism at the molecular level2-8. In contrast, hydroxide ion mobility in basic solutions has received far less attention2,3,9,10, even though bases and base catalysis play important roles in many organic and biochemical reactions and in the chemical industry. The reason for this may be attributed to the century-old notion11 that a hydrated OH- can be regarded as a water molecule missing a proton, and that the transport mechanism of such a 'proton hole' can be inferred from that of an excess proton by simply reversing hydrogen bond polarities11-18. However, recent studies2,3 have identified OH- hydration complexes that bear little structural similarity to proton hydration complexes. Here we report the solution structures and transport mechanisms of hydrated hydroxide, which we obtained from first-principles computer simulations that explicitly treat quantum and thermal fluctuations of all nuclei19-21. We find that the transport mechanism, which differs significantly from the proton hole picture, involves an interplay between the previously identified hydration complexes2,3 and is strongly influenced by nuclear quantum effects.",
author = "Mark Tuckerman and Dominik Marx and Michele Parrinello",
year = "2002",
month = "6",
day = "27",
doi = "10.1038/nature00797",
language = "English (US)",
volume = "417",
pages = "925--929",
journal = "Nature",
issn = "0028-0836",
publisher = "Nature Publishing Group",
number = "6892",

}

TY - JOUR

T1 - The nature and transport mechanism of hydrated hydroxide ions in aqueous solution

AU - Tuckerman, Mark

AU - Marx, Dominik

AU - Parrinello, Michele

PY - 2002/6/27

Y1 - 2002/6/27

N2 - Compared to other ions, protons (H+) and hydroxide ions (OH-) exhibit anomalously high mobilities in aqueous solutions. On a qualitative level, this behaviour has long been explained by 'structural diffusion' - the continuous interconversion between hydration complexes driven by fluctuations in the solvation shell of the hydrated ions. Detailed investigations have led to a clear understanding of the proton transport mechanism at the molecular level2-8. In contrast, hydroxide ion mobility in basic solutions has received far less attention2,3,9,10, even though bases and base catalysis play important roles in many organic and biochemical reactions and in the chemical industry. The reason for this may be attributed to the century-old notion11 that a hydrated OH- can be regarded as a water molecule missing a proton, and that the transport mechanism of such a 'proton hole' can be inferred from that of an excess proton by simply reversing hydrogen bond polarities11-18. However, recent studies2,3 have identified OH- hydration complexes that bear little structural similarity to proton hydration complexes. Here we report the solution structures and transport mechanisms of hydrated hydroxide, which we obtained from first-principles computer simulations that explicitly treat quantum and thermal fluctuations of all nuclei19-21. We find that the transport mechanism, which differs significantly from the proton hole picture, involves an interplay between the previously identified hydration complexes2,3 and is strongly influenced by nuclear quantum effects.

AB - Compared to other ions, protons (H+) and hydroxide ions (OH-) exhibit anomalously high mobilities in aqueous solutions. On a qualitative level, this behaviour has long been explained by 'structural diffusion' - the continuous interconversion between hydration complexes driven by fluctuations in the solvation shell of the hydrated ions. Detailed investigations have led to a clear understanding of the proton transport mechanism at the molecular level2-8. In contrast, hydroxide ion mobility in basic solutions has received far less attention2,3,9,10, even though bases and base catalysis play important roles in many organic and biochemical reactions and in the chemical industry. The reason for this may be attributed to the century-old notion11 that a hydrated OH- can be regarded as a water molecule missing a proton, and that the transport mechanism of such a 'proton hole' can be inferred from that of an excess proton by simply reversing hydrogen bond polarities11-18. However, recent studies2,3 have identified OH- hydration complexes that bear little structural similarity to proton hydration complexes. Here we report the solution structures and transport mechanisms of hydrated hydroxide, which we obtained from first-principles computer simulations that explicitly treat quantum and thermal fluctuations of all nuclei19-21. We find that the transport mechanism, which differs significantly from the proton hole picture, involves an interplay between the previously identified hydration complexes2,3 and is strongly influenced by nuclear quantum effects.

UR - http://www.scopus.com/inward/record.url?scp=0037182850&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0037182850&partnerID=8YFLogxK

U2 - 10.1038/nature00797

DO - 10.1038/nature00797

M3 - Article

VL - 417

SP - 925

EP - 929

JO - Nature

JF - Nature

SN - 0028-0836

IS - 6892

ER -