WATER A COMPREHENSIVE TREATISE

Volume 6

Recent Advances

Volume

Volume 2

Volume 3

Volume 4

Volume 5

Volume 6

WATER A COMPREHENSIVE TREATISE

Edited by Felix Franks

The Physics and Physical Chemistry of Water

Water in Crystalline Hydrates; Aqueous Solutions of Simple Nonelectrolytes

Aqueous Solutions of Simple Electrolytes

Aqueous Solutions of Amphiphiles and Macromolecules

Water in Disperse Systems

Recent Advances

WATER A COMPREHENSIVE TREATISE

Edited by Felix Franks Department of Botany

University of Cambridge Cambridge, England

Volume 6 Recent Advances

PLENUM PRESS • NEW YORK AND LONDON

Library of Congress Cataloging in Publication Data

Franks, Felix. Water: a comprehensive treatise.

Includes bibliographies. CONTENTS: v. 1. The physics and physical chemistry of water.

-v. 2. Water in crystalline hydrates; aqueous solutions of simple nonelec­trolytes.-[etc.)-v. 6. Recent advances.

1. Water. I. Title. QD169.W3F7 546'.22 78-165694 ISBN 978-1-4684-8020-7 ISBN 978-1-4684-8018-4 (eBook)

DOl 10_1007/978-1-4684-8018-4

©1979 Plenum Press, New York Softcover reprint of the hardcover 1st edition 1979 A Division of Plenum Publishing Corporation 227 West 17th Street, New York, N_Y. 10011

All rights reserved

No part of this book may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electronic, mechanical, photocopying, microfilming,

recording, or otherwise, without written permission from the Publisher

Preface

Since the publication of the previous volumes many new aspects of the physical and life sciences have been developed in which the properties of water play a dominant role.

Although, according to its preface, Volume 5 was to be the last one of the treatise, these recent developments have led to a revision of that statement. The present volume and its companion, still in preparation, deal with topics that were already mentioned in the preface to Volume 5 as gaining in importance.

The recent development of X-ray and, more particularly, neutron scattering techniques have led to studies of "structure" in aqueous solutions of electrolytes on the one hand, and to the role of water in protein structure and function on the other. Both these topics have reached a stage where reviews of the present state of knowledge are useful.

The application of ab initio methods to calculations of hydration and conformation of small molecules has a longer history, but here again a critical summary is timely.

The role of solvent effects in reaction kinetics and mechanisms should have had a place in Volume 2 of this treatise, but, as sometimes happens, the author who had taken on this task failed tQ live up to his promise. However, since 1972 the physical chemistry of mixed aqueous solvents has made considerable strides, so that the belated discussion of this topic (by a new author) is built on evidence that was not available at the time of publication of Volume 2.

Hand in hand with the development of more penetrating experimental techniques there have been developments in theoretical approaches and computer simulation methods to probe the nature of the liquid state in general, and of water in particular. This volume therefore includes contribu­tions on both these topics. At the time of writing it seems that the "hydro­phobic" effect is still a topic of great importance; it crops up in several of the chapters constituting this volume, and it is at last being considered worthy of study by the theoreticians.

v

vi Preface

Of necessity, this volume, as distinct from its predecessors, has the character of a "Recent Advances" publication, the connecting thread being water. It becomes clear that we are still far from appreciating fully the extent to which the eccentric properties of water shape many physico­chemical and most biochemical processes that are normally studied without due regard to solvent effects.

Once again it is a pleasure to thank Joyce Johnson for her willing and cheerful cooperation in the editorial work. I also thank the contributing authors, some of whom produced manuscripts at quite short notice.

My main debt of gratitude goes to my wife Hedy for her constant support, practical and spiritual, during the preparation of this volume, which coincided with a very difficult and upsetting period of my profes­sional life.

Department of Botany University of Cambridge

FELIX FRANKS

Contents

Contents of Earlier Volumes

Chapter 1

X-Ray and Neutron Scattering by Aqueous Solutions of Electrolytes

J. E. Enderby and G. W. Neilson

1. The Basic Structural Problem 1.1. Introduction . . . . . . 1.2. The Properties of S 1X{J(k) • 1.3. Termination Errors

2. X-Ray Studies 2.1. Introduction 2.2. A Survey of X-Ray Studies 2.3. Future Prospects

3. Neutron Studies. . . . . . . . 3.1. Introduction . . . . . . . 3.2. First-Order Difference Scattering Functions 3.3. Placzek Corrections to the First-Order Difference LlMO(k) 3.4. Experimental Procedures . . . . . . . . . . 3.5. Second-Order Difference Scattering Functions . . 3.6. Experimental Procedures . . . . . . . . . . . .

4. Structural Information Derived from Neutron Studies 4.1. Introduction 4.2. Cationic Hydration . . . . . . . . 4.3. Anionic Hydration . . . . . . . . 4.4. Cation-Cation Distribution Functions 4.5. Anion-Anion Distribution Functions

5. Conclusions and Future Prospects

vii

xiii

1 1 4 7

7 7 9

16

17 17 20 21 23 24 25

25 25 27 33 38 42

44

viii

Chapter 2

The Organization and Function of Water in Protein Crystals

J. L. Finney

1. Introduction . . . . . . . . . . . . . . .

2. Water-Water and Water-Protein Interactions 2.1. Possible Solvent Effects in Proteins . . . 2.2. Conventional Wisdom of Protein Hydration

3. Crystal Structure Analysis of Proteins and Its Subsequent

Contents

47

50 53 59

Refinement . . . . . . . . . . . . . . . . . . . . . 61 3.1. Theory, Data Collection, and Initial Solution of the Structure 62 3.2. Refinement of Structure . . . . . . . . . . . . 65 3.3. Summary: Reliability of Atomic Coordinate Data 68

4. Solvent Information from Crystal Structure Analysis 69 4.1. Information from Protein Coordinates 69 4.2. Direct Location of Water Molecules 81 4.3. Water in the Outer Solvent Region. . 108

5. Summary: What We Think We Now Know. 115

6. Current Work and Future Developments 118 6.1. Experimental Work 118 6.2. Theoretical Work . . 120

Chapter 3

Ab Initio Methods and the Study of Molecular Hydration

W. Graham Richards

I. Introduction

2. Monomeric Water.

3. The Water Dimer .

4. Polymers of Water

5. Solvated Ion Pairs

6. Solvation of Molecules and Ions 6.1. The Supermolecule Approach 6.2. The Continuum Approach . . 6.3. The Statistical Approach Using Solvation

7. Conclusions. . . . . . . . . . . . . . . .

Potentials

123

124

124

127

129

129 130 134 136

137

Contents

Chapter 4

Mixed Aqueous Solvent Effects on Kinetics and Mechanisms of Organic Reactions

J. B. F. N. Engberts

1. Introduction . . . . . .

2. Mixed Aqueous Solutions 2.1. Classification . . . . 2.2. Solvent Parameters

3. Solute-Solvent Interactions in Mixed Aqueous Solutions 3.1. Hydrogen Bonding . . . . 3.2. Hydrophobic Interactions

ix

139

144 144 147

159 160 164

3.3. van der Waals Interactions. 166 3.4. Electrostatic Interactions . . 167 3.5. Treatments of Solution Processes in Aqueous Media 168

4. Mixed Aqueous Solvent Effects and Transition-State Theory 171 4.1. Transition-State Theory . .. ..... 171 4.2. Activation Parameters . . .. ..... 172 4.3. Solvent Effects on Initial State and Transition State 176 4.4. Isokinetic Relationships . . . 179

5. Kinetic Solvent Effects on Organic Reactions in Mixed Aqueous Solvents . . . . . . . . . . 181 5.1. Introduction 5.2. Water-Catalyzed Reactions 5.3. Acid- and Base-Catalyzed Reactions 5.4. Nucleophilic Displacement Reactions 5.5. Miscellaneous Reactions . . . . . .

Chapter 5

Solvent Structure and Hydrophobic Solutions

D. Y. C. Chan, D. J. Mitchell, B. W. Ninham, and B. A. Pailthorpe

1. Introduction

2. Thermodynamics: Formalism and Notation 2.1. Definitions 2.2. Thermodynamics and Distribution Functions . 2.3. Remarks on Structure

181 181 210 220 230

239

241 241 242 244

x

3. Solvent Structure and Solution Thermodynamics: Models 3.1. Characterization of Hydrophobic Solutions 3.2. Effects of Molecular Properties 3.3. Hard-Sphere Mixtures . 3.4. One-Dimensional Solutions.

4. Evidence from van der Waals Forces 4.1. Many-Body Forces 4.2. Temperature-Dependent Forces and Salt Effects

5. Effect of Solvent Structure on Long-Range Forces 5.1. Solute Interactions via Lifshitz Theory 5.2. Planar Interactions via Statistical Mechanics

6. Short-Range Solute-Solute Interaction. 6.1. Hard-Sphere Solvent. 6.2. Lennard-Jones Solvent 6.3. Sticky Hard Spheres. 6.4. Finite-Size Solutes .

7. Mean-Field Theory of Solvent Structure.

8. Conclusion

Chapter 6

Computer Simulation of Water and Aqueous Solutions

D. W. Wood

I. Introduction

Contents

245 246 247 248 250

256 258 259

261 261 263

265 266 266 268 270

271

276

279

2. Some Aspects of Statistical Mechanics for Molecular Assemblies 280

3. The Molecular Dynamics Method .... 288

4. ModeJs of the Water Molecule. . . . . . 306 4.1. The Ben-Nairn-Stillinger (BNS) Model 307 4.2. The ST2 Potential. . . . . . . . . 310 4.3. Hartree-Fock Potential 4.4. Point Charge Models for Monomers 4.5. Central-Force Models . . .

5. Potentials for Aqueous Solutions 5.1. Solutions of Inert Atoms 5.2. Ionic Solutions . . . . . . 5.3. Organic Molecules and Water

312 325 327

332 332 333 341

Contents

6. Molecular Dynamics Studies of Pure Water 6.1. Equilibrium Structure . . . . . . . 6.2. Kinetic Properties . . . . . . . . . .

7. Monte Carlo Simulations of Pure Water

8. Molecular Dynamics Results for Aqueous Solutions

9. Monte Carlo Results for Aqueous Solutions .

Appendix ................. .

References. .

Author Index

Subject Index

Compound Index .

xi

346 347 365 372 378 386 392

411

437

447

453

Contents of Earlier Volumes

Volume 1: The Physics and Physical Chemistry of Water

Chapter 1. Introduction-Water, the Unique Chemical, by F. Franks Chapter 2. The Water Molecule, by C. W. Kern and M. Karplus Chapter 3. Theory of Hydrogen Bonding in Water, by C. N. R. Rao Chapter 4. The Properties of Ice, by F. Franks Chapter 5. Raman and Infrared Spectral Investigations of Water Structure,

by G. E. Walrafen Chapter 6. Nuclear Magnetic Resonance Studies 'On Water and Ice, by Jay

A. Glasel Chapter 7. Liquid Water: Dielectric Properties, by J. B. Hasted Chapter 8. Liquid Water: Scattering of X-Rays, by A. H. Narten and H. A.

Levy Chapter 9. The Scattering of Neutrons by Liquid Water, by D. I. Page Chapter 10. Thermodynamic and Transport Properties of Fluid Water, by G. S.

KeII Chapter 11. Application of Statistical Mechanics in the Study of Liquid Water,

by A. Ben-Nairn Chapter 12. Liquid Water-Acoustic Properties: Absorption and Relaxation, by

Charles M. Davis, Jr., and Jacek Jarzynski Chapter 13. Water at High Temperatures and Pressures, by Klaus Todheide Chapter 14. Structural Models, by Henry S. Frank

Volume 2: Water in Crystalline Hydrates; Aqueous Solutions of Simple Nonelectrolytes

Chapter 1. The Solvent Properties of Water, by F. Franks Chapter 2. Water in Stoichiometric Hydrates, by M. Falk and O. Knop Chapter 3. Clathrate Hydrates, by D. W. Davidson Chapter 4. Infrared Studies of Hydrogen Bonding in Pure Liquids and Solu­

tions, by W. A. P. Luck Chapter 5. Thermodynamic Properties, by F. Franks and D. S. Reid Chapter 6. Phase Behavior of Aqueous Solutions at High Pressures, by G. M.

Schneider Chapter 7. Dielectric Properties, by J. B. Hasted

xiii

xiv Contents of Earlier Volumes

Chapter 8. Spectroscopic Properties, by M. J. Blandamer and M. F. Fox Chapter 9. Acoustic Properties, by M. J. Blandamer Chapter 10. NMR Spectroscopic Studies, by M. D. Zeidler Chapter 11. Molecular Theories and Models of Water and of Dilute Aqueous

Solutions, by A. Ben-Naim

Volume 3: Aqueous Solutions of Simple Electrolytes

Chapter 1. Thermodynamics of Ion Hydration, by H. Friedman and C. V. Krishnan

Chapter 2. Thermodynamics of Aqueous Mixed Electrolytes, by H. L. Anderson and R. H. Wood

Chapter 3. Hydration Effects in Acid-Base Equilibria, by L. G. Hepler and E. M. Woolley

Chapter 4. Ion Transport in Water and Mixed Aqueous Solvents, by R. L. Kay Chapter 5. Infrared Spectroscopy of Aqueous Solutions, by R. E. Verrall Chapter 6. Raman Spectroscopy of Aqueous Electrolyte Solutions, by T. H.

Lilley Chapter 7. Nuclear Magnetic Relaxation Spectroscopy, by H. G. Hertz Chapter 8. Dielectric Properties, by R. Pottel

Volume 4: Aqueous Solutions of Ampbipbiles and Macromolecules

Chapter 1. The Hydrophobic Interaction, by F. Franks Chapter 2. Surfactants, by G. C. Kresheck Chapter 3. Dyestuffs, by G. H. Giles and D. G. Duff Chapter 4. Lipids, by H. Hauser Chapter 5. Nucleic Acids, Peptides, and Proteins, by D. Eagiand Chapter 6. Polysaccharides, by A. Suggett Chapter 7. Synthetic Polymers, by P. Molyneux

Volume 5: Watet in Disperse Systems

Chapter 1. The Influence of Hydration on the Stability of Hydrophobic Col­loidal Systems, by D. Eagland

Chapter 2. Properties of Water in Capillaries and Thin Films, by J. Clifford Chapter 3. Hydration and the Stability of Foams and Emulsions, by M. C.

Phillips Chapter 4. Clay-Water Systems, by Erik Forslind and Arvid Jacobsson Chapter 5. Adsorption of Water on Well-Characterized Solid Surfaces, by A.

C. Zettlemoyer, F. J. Micale, and K. Klier Chapter 6. Specific Interactions of Water with Biopolymers, by Herman J. C.

Berendsen