Page 230 - MODERN ELECTROCHEMISTRY

166 CHAPTER 2

The basic idea ofcalculating a hydration number is to study the number of water
molecules in the shell as a function of time. At t = 0, the number is the coordination
number, and at all the waters have been replaced. Then the mean number
during this time is taken as the solvation number:

where is the residence time for water around water. Although this approach
does not take into account the distribution of residence times for the various waters
“caught” in different positions when the ions arrive, it does give reasonable values
(Table 2.27).

Further Reading

Seminal
1. J. O’M. Bockris and P. P. S. Saluja, “The Time Dependence of Solvation Numbers,” J.
Electrochem. Soc. 119: 1060(1972).
2. G. Palinkas, W. O. Riede, and K. Heinzinger, “Calculation of Distribution Functions,” Z.
Naturforsch. 32: 1137 (1972).
3. F. H. Stillinger and A. Rahman, “A Statistical Mechanical Approach to Ionic Solution,”
J. Chem. Phys. 60: 1545 (1974).

Papers
1. A. Chandra and B. Bagchi, J. Phys. Chem. 93: 6996 (1989).
2. E. Guardia and J. A. Padro, J. Phys. Chem. 94: 2113 (1990).
3. P. Cieplak and P. Kollman, J. Chem. Phys. 92: 6761 (1990).
4. P. A. Kollman, J. Am. Chem. Soc. 113: 2681 (1991).
5. T. Yabe, S. Sankareman, and J. K. Kochi, J. Phys. Chem. 95: 4147 (1991).
6. H. Yu, B. M. Pettitt, and M. Karplus, J. Am. Chem. Soc. 113: 2425 (1991).
7. R. W. Rick and B. J. Berne, J. Am. Chem. Soc. 116: 3949 (1994).
8. P. J. Rossky, K. P. Johnson, and P. B. Babuena, J. Phys. Chem. 100: 2706 (1996).
9. C. C. Pye, W. Rudolph, and R. A. Pourier, J. Phys. Chem. 100: 601 (1996).
10. T. Z. M. Denti, T. C. Beutler, W. F. Vangunsteeren, and F. Diedrich, J. Phys. Chem. 100:
4256 (1996).

2.20. INTERACTIONS OF IONS WITH NONELECTROLYTES IN
SOLUTION

2.20.1. The Problem
The picture that has emerged in this book so far is of ions interacting with a solvent
and producing the interesting effects that go under the name “solvation.” The solvent