1392
Additions and Corrections
where uWateror uIattice is the volume fraction of water or of dry zeolite in the powder. We also assume t h a t the specific polarization is related to the permittivity by the Kirkwood expression: l 2 p =
(c’
translational “mobilities”, estimated from N M R data, only twenty times lower than molecules in t h e bulk phase.
References and Notes H. A. Resing, Adv. Mol. Relaxation Processes, 3, 199-266 (1972). H. A. Resing and J. S. Murday, Adv. Chem. Ser., No. 121, 414-429 (1973). H. A. Resing. J. Phys. Chem.. 80, 186 (1976). F. J. Jansen, Thesis, Katholieke Universiteit Leuven, Belgium, 1972: F. J. Jansen and R. A. Schoonheydt, Adv. Chem. Ser., No. 121, 96-105 (1973). J. B. Hasted, D. M. Ritson, and C. H. Collie, J. Chem. Phys., 16, 1-21 (1948). J. A. Lane and J. A. Saxton, Proc. R. SOC.London, Ser. A, 214, 531545 (1952). D. W. Breck, J. Chem. Educ., 41, 678-687 (1964). N. E. Hill, Ed., “Dielectric Properties and Molecular Behaviour”, Van Nostrand-Reinhold, New York. N.Y., 1969, p 56. V. K. Benzar and I. M. Rimkevitch, J. Phys. Chem. USSR, 47, 435-436 (1973). C. T. O’Konski and A . Edwards, Rev. Sei. Instrum., 39, 1456-1458 (1968). R. A. Schoonheydt. personal communication. N. Hill, ref 8, p 427.
- 1)(2c’+ 1)/9c’
Although this formula is essentially empirical, it has been successfully used in other studies of adsorbed molecules,12 a n d it predicts a bulk permittivity of 6.3 for dehydrated zeolite NaX, in good agreement with other estimates4 Table I shows the results of these calculations. We find t h e maximum apparent permittivity of t h e interstitial water in NaX and NaY to be about 14 and 21, respectively, a t 298 K. Assuming that t h e Na+ cations are more strongly hydrated than either the lattice 0- charges (in the zeolite) or than simple anions (in bulk solution), our results can be compared to previous measurements of the permittivity of concentrated NaCl aqueous solutions (Figure 2). Although extensive association undoubtedly occurs between the lattice 0- ions and the mobile Na+ counterions, most of the interstitial water molecules are probably located in the primary hydration spheres of these two ion species. Our results show that these water dipoles are “immobilized” (in the sense t h a t their dipole moments do not contribute to the polarizability of the crystal), yet have rotational and
A r m e d Forces Radiobiology Research institute Bethesda, Maryland 200 14
Kenneth R. Foster
Naval Research Laboratory Washington, D.C. 20375 Received October 6, 1975
Henry A. Resing’
ADDITIONS AND CORRECTIONS 1975, Volume 79
Ira B. Goldberg, Harry R. Crowe, and Richard W. Franck: Peri Interactions in the Tetra-tert-butyl- and 1,3,8-Tri-tert-butylnaphthalene Anions. An Electron Spin Resonance Study. Page 1744, Table 111. The g factors of all of the naphthalene anions were based on the value of 2.002657 for t h e g factor of the perylene anion. T h e value of the g factor and g - g, for the naphthalene anion should be corrected to read 2.002736 and respectively.-Ira B. Goldberg 0.417 x 1975, Volume 79
J. L. Dye, C. W. Andrews, and S. E. Mathews: Strategies for the Preparation of Compounds of Alkali Metal Anions. Page 3068. Table IV has been revised as follows: TABLE IV: Estimated Enthalpy Changes for Various Reaction Steps M-M distance in Metal metal, A
Li Na K Rb cs
3.04 3.72 4.54 4.95 5.31
Enthalpy change, kcal mol-’ (see Figure 2)
Radius Of
AH,,,
AH,p
AH,,
AHl,
AHF
crwtated cat‘ion, %,
38.4 25.8 21.3 19.5 18.7
124.3 118.5
-14.3 -12.6 -11.6 -11.2 -10.9
-175.6 -143.8 -118.0 -108.3 -101.1
11.2 13.7 13.1 15.8 15.2
5.06 5.50 5.52 5.53 5.56
100.1 96.3 89.8
-J. L. Dye The Journal of Physical Chemistry, Vol. 80. No. 12. 1976
-
(mo9
( M 0 9
-
AHOio,
Uog’)max,
AH‘g‘)est!
kcal mol-’
kcal mol-’
kcal
-74.2 -67.6 -64.4 -62.6 -61.3
-19.4 21.5 25.8 30.4
mol-’
-22.2 14.9 21.4 37.6
