39111
ADDITIONS AND CORRECTIONS
1!963, Volume 67 Bernard J. Wood, James S. Mills, and Henry Wise: Energy Accommodation in Exothermic Heterogeneous Catalytic Reactions. Pages 1463-1465. Two errors, perpetrated in the derivations of the expressions relating the number densities of oxygen molecules and hydrogen atoms to their respective e.p.r. line intensities, affect the numerical values of the reaction energy accommodation coefficient, p . These errors were revealed to us by the analysis of Westenberg and de Haas in a recent paper [ J . Chem. Phys., 40, 3087 (1964)l. We are grateful to these authors for their courtesy in providing us with a preprint of their contribution. The term g,ff in the denominator of eq. 1 is incorrect as it stands and should be replaced by gZ/geff where g, the Lande factor, is 2.0023. Then, in eq. 3, geff/g becomes g/geff. Because of an erroneouts evaluation of the appropriate matrix element for atomic hydrogen, the right-hand side of eq. 2 is too large by a factor of 2. Hence, a 2 should appear in the denominator in eq. 3. The value of geff = (h/B)(dv/dH) is 1.40 for the particular 0, transition observed in this study. In the paper, the quotient h/B was inadvertently omitted from the definition of geff, whicb led to the use of an incorrect value of 1.96 for geff. Inserting the correct value for g,ff into the correct form of eq. 3 changes the values of the numerical coefficients in eq. 4 and 5 to 1.96 X 10--2 and 6.33 X 1014, respectively. Since N H appears in the denominator of eq. 13, the values of p reported in the paper should be increased by a factor of 2.68/1.96 = 1.37. The corrected values are tabulated below.
Page 2274. The numbers on the ordinates of Fig. 1 and 2 are incorrect and should start from the origin 0, 1, 2, . . . instead of 1, 2, 3, . . .. Page 2275. In footnote 8, the coefficients of ( R , )in the surnmation in the denominator are u,~,~/~,E.--RIcHARDA. HOLROYD.
A. Chakravorty and F. A. Cotton: Stability Constants and Structures of Some Metal Complexes with Imidazole Derivatives. Page 2879. Line 9 should read: Each solution was initially 0.001 M in metal ion, 0.002 M in ligand, 0.005 M in HC104, arid 0.2 M in KNOa. Lines 26-29 should read: Further, the present titrations were done in complete absence of chloride ions, so that any possible formation of chloro complexes was completeYy avoided.- A. CHAKRAVORTY. 1964; Volume 68 Peter J. Dunlop: Frictional Coefficients for Binary and Ternary Isothermal Diffusion. Page 27. The second line above eq. 9 should read:. . . but that only q are indepenldently since. . . . Equation 9 should read
PETERJ. DUNLOP H. David Ellerton, Gundega Reinfelds, Dennis E. Mulcahy, and Peter J. Dunlop: Activity, Density, and Relative Viscosity Data for Several Amino Acids, Lactamide, and Raffinose in Aqueous Solution a t 25'. Page 400. In Table 11, heading, . . . us. molarity a t 25' should read . . us. molality at 25". Column 2, next to last line: combining eq. 1 and 2 . . . should read combining eq. 3 and 4 . . . . Page 401. Column 1, eq. 5 should read
.
Table I : Corrected Valueis of Reaction Energy Accommodation Coefficient, 8, for Hydrogen Atom Recombination on Metals Catalytic surface
Temp.,
OK.
8 (average)
Nickel
423
0 . 8 2 =!C 0 . 1 5
Tungsten
443 480 773
1 . 0 8 f 0.11 1 . 1 1 f 0.07 1.17 f 0 . 1 8
376 378 588 813
0.67 0.78 0.34 0.26
Platinum
f 0.10 f 0.10 =!C 0 . 0 4 f 0.03
Page 1463. I n footnote 8, the page number and year should be 1196 (1959) instead of 1788 (1961). Page 1464. In eq. 9, the term Dl2 in the denominator should be deleted.-BERNARD J. W O O D . Richard A. Holroyd and (George W. Klein: -Mercury-Photosensitized Decomposition of Aliphatic Hydrocarbons-Radical Detection with Ethyl-Carbon-14 Radicals.
PETERJ. DUNLOP Thomas B. Hoover: Conductance of Potassium Chloride in Highly Purified N-Methylpropionamide from 20 to 40'. Page 877. In the paragraph headed "Dielectric Constant," the phrase in parentheses should read (the conductance cell constant corresponds to 3.24 pf.). Page 878. In Table 11, columns headed A are actually A?', as defined by eq. 6. A corrected table of molar conductances will be supplied by the author upon request.-THOMAS B. HOOVER. Maurizio Cignitti and Thomas L. Allen: Nonbonded Interactions and the Internal Rotation Barrier. Page 1292. K. S. Pitzer has pointed out to us that the conclusion of Blade and Kimball (mentioned in the Introduction) concerning the uncertaint3yabout the shape of the ethane internal rotation barrier was erroneous, as explained by him in the following year [Discussions Faraday SOC.,10, 66 (1951)]. None of the
Volume 68, Number 12
December, 1964
