Water In Crystalline Hydrates Aqueous Solutions Of Simple Nonelectrolytes

vi the information collected and discussed in this volume may help toward the achievement of such an objective. I should like to express my debt of gratitude to the authors who have contributed to this volume. Editing a work of this nature can strain long established personal relationships and I thank my various colleagues for bearing with me and responding (sooner or later) to one or several letters or telephone calls. My special thanks once again go to Mrs. Joyce Johnson, who bore the main brunt of this seemingly endless correspondence and without whose help the editorial and referencing work would have taken several years. F. FRANKS Biophysics Division Unilever Research Laboratory Colworth/ Welwyn Colworth House, Sharnbrook, Bedford January, 1973 Contents Contents of Volume 1 ............................. . . . . . .. . . .. xv Contents of Volume 3 ........................ '. . . . . . . . . . . . xvi . . . . Contents of Volume 4 . . . . . . . . . . . . . . . . . . . . . . . . .. . . . xvii . . . . . . . . . . . Chapter 1 The Solvent Properties of Water F. Franks 1. Water, the Universal Solvent-the Study of Aqueous Solutions 2. Aqueous Solutions of Nonelectrolytes ................. . 5 2.1. Apolar Solutes ................................. . 6 2.2. Polar Solutes .................................. . 19 2.3. Ionic Solutes Containing Alkyl Residues-"Apolar Electrolytes" ................................... . 38 3. Aqueous Solutions of Electrolytes .................... . 42 3.1. Single Ion Properties ............................ . 42 3.2. Ion-Water Interactions ......................... . 43 3.3. Interionic Effects ............................... . 47 4. Complex Aqueous Mixtures 48 Chapter 2 Water in Stoichiometric Hydrates M. Falk and O. Knop 1. Introduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55 . . . . . . . . . . . . . 2. Symmetry and Types of Environment of the H0 Molecule 2 in Crystals .......................................... 57 vii Contents viii 2.1. Site Symmetry. . . . . . . . . . . . . . . . . . . . . . . . . 57 . . . . . . . . . .

The chapters making up this volume had originally been planned to form part of a single volume covering solid hydrates and aqueous solutions of simple molecules and ions. However, during the preparation of the manu scripts it became apparent that such a volume would turn out to be very unwieldy and I reluctantly decided to recommend the publication of sepa rate volumes. The most sensible way of dividing the subject matter seemed to lie in the separation of simple ionic solutions. The emphasis in the present volume is placed on ion-solvent effects, since a number of excellent texts cover the more general aspects of electrolyte solutions, based on the classical theories of Debye, Huckel, On sager, and Fuoss. It is interesting to speculate as to when a theory becomes "classical." Perhaps this occurs when it has become well known, well liked, and much adapted. The above-mentioned theories of ionic equilibria and transport certainly fulfill these criteria. There comes a time when the refinements and modifications can no longer be related to physical significance and can no longer hide the fact that certain fundamental assumptions made in the development of the theory are untenable, especially in the light of information obtained from the application of sophisticated molecular and thermodynamic techniques.

This Volume, the last of the series, is devoted to water in its metastable forms, especially at sub-zero temperatures. The past few years have wit nessed an increasing interest in supercooled water and amorphous ice. If the properties of liquid water in the normal temperature range are already eccentric, then they become exceedingly so below the normal freezing point, in the metastable temperature range. Water can be supercooled to -39°C without too much effort, and most of its physical properties show a re markable temperature dependence under these conditions. Although ade quate explanations are still lacking, the time has come to review available knowledge. The study of amorphous ice, that is, the solid formed when water vapor is condensed on a very cold surface, is of longer standing. It has achieved renewed interest because it may serve as a model for the liquid state. There is currently a debate whether or not a close structural relation ship exists between amorphous ice and supercooled water. The nucleation and growth of ice in supercooled water and aqueous solutions is also still one of those grey areas of research, although these topics have received considerable attention from chemists and physicists over the past two decades. Even now, the relationships between degree of supercooling, nucleation kinetics, crystal growth kinetics, cooling rate and solute concentration are somewhat obscure. Nevertheless, at the empirical level much progress has been made, because these topics are of considerable importance to biologists, technologists, atmospheric physicists and gla ciologists.

Annotation. Specialist Periodical Reports provide systematic and detailed review coverage of progress in the major areas of chemical research. Written by experts in their specialist fields the series creates a unique service for the active research chemist, supplying regular critical in-depth accounts of progress in particular areas of chemistry. For over 80 years the Royal Society of Chemistry and its predecessor, the Chemical Society, have been publishing reports charting developments in chemistry, which originally took the form of Annual Reports. However, by 1967 the whole spectrum of chemistry could no longer be contained within one volume and the series Specialist Periodical Reports was born. The Annual Reports themselves still existed but were divided into two, and subsequently three, volumes covering Inorganic, Organic and Physical Chemistry. For more general coverage of the highlights in chemistry they remain a 'must'. Since that time the SPR series has altered according to the fluctuating degree of activity in various fields of chemistry. Some titles have remained unchanged, while others have altered their emphasis along with their titles; some have been combined under a new name whereas others have had to be discontinued.

Specialist Periodical Reports provide systematic and detailed review coverage of progress in the major areas of chemical research. Written by experts in their specialist fields the series creates a unique service for the active research chemist, supplying regular critical in-depth accounts of progress in particular areas of chemistry. For over 80 years the Royal Society of Chemistry and its predecessor, the Chemical Society, have been publishing reports charting developments in chemistry, which originally took the form of Annual Reports. However, by 1967 the whole spectrum of chemistry could no longer be contained within one volume and the series Specialist Periodical Reports was born. The Annual Reports themselves still existed but were divided into two, and subsequently three, volumes covering Inorganic, Organic and Physical Chemistry. For more general coverage of the highlights in chemistry they remain a 'must'. Since that time the SPR series has altered according to the fluctuating degree of activity in various fields of chemistry. Some titles have remained unchanged, while others have altered their emphasis along with their titles; some have been combined under a new name whereas others have had to be discontinued.

to arrive at some temporary consensus model or models; and to present reliable physical data pertaining to water under a range of conditions, i.e., "Dorsey revisited," albeit on a less ambitious scale. I should like to acknowledge a debt of gratitude to several of my col leagues, to Prof. D. J. G. Ives and Prof. Robert L. Kay for valuable guidance and active encouragement, to the contributors to this volume for their willing cooperation, and to my wife and daughters for the understanding shown to a husband and father who hid in his study for many an evening. My very special thanks go to Mrs. Joyce Johnson, who did all the cor respondence and much of the arduous editorial work with her usual cheerful efficiency. F. FRANKS Biophysics Division Unilever Research Laboratory ColworthjWelwyn Colworth House, Sharnbrook, Bedford March 1972 Contents Chapter 1 Introduction-Water, the Unique Chemical F. Franks I. lntroduction ........................................ . 2. The Occurrence and Distribution of Water on the Earth 2 3. Water and Life ...................................... 4 4. The Scientific Study of Water-A Short History ........ 8 5. The Place of Water among Liquids . . . . . . . . . . . . . . . 13 . . . . . Chapter 2 The Water Moleeule C. W. Kern and M. Karplus 1. Introduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 . . . . . . . . . . 2. Principles of Structure and Spectra: The Born-Oppenheimer Separation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 . . . . . . . . . . . . 3. The Electronic Motion ............................... 26 3.1. The Ground Electronic State of Water ............ 31 3.2. The Excited Electronic States of Water ........... 50 4. The Nuclear Motion ................................. 52 5. External-Field Effects ................................. 70 5.1. Perturbed Hartree-Fock Method . . . . . . . . . . . . . . . 74 . . .