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COMMUNICATIONS TO THE EDITOR
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Vol. 60
tra on solutions of I in CHC&indicated stretching This may be seen from Table IV, where K between of the phosphoryl bond, which was attributable to I and the organic solvent is assigned a value of hydrogen bondingas unity. The high solubility of I in chlorobenzene, rel& TABLE IV tive to its solubility parameter in Table 111,is likeRATIO OF DISTRIBUTION COEFFICIENTS (BENZENETO wise attributed to a hydrogen bonding capacity, albeit small. The higher solubility of I in nitro- WATER A N D Sym-TITTRACELOROETHANE TO W A T E R ) OF PHOSPHONOFLUORID ATES propane as as compared t o nitrobenzene and in Phosphonofluoridates nitrobenzene as compared to chlorobenzene may IV I11 I1 I Solvent pair be correlated with the electron densities of the Benzene/HzO 21: 19.7: 3 . 5 : 1 bonding hydrogens as influenced by the inductive sym-Tetraobloroethse/H20 28.2: 21.6: 4 . 1 : 1 effects of the electronegative groups and the disSince there is little or no possibility for hydrogen tance of these groups from the bonding hydrogen. The K’s for I, 11, I11 and IV between sym-tetra- bonding in the benzene-water system, the increasc chloroethane and water show an increase in solu- in K is attributed for the most part to an increase bility of the solute in the organic solvent with in- in the size of the alkyl groups on the phosphonocreasing molecular weight of the phosphonofluori- fluoridate, (thus increasing the lipoid solubility and date. Approximately the same proportional in- decreasing the water solubility of the phosphonocrease in K is found with the benzene-water pair. fluoridate) rather than to a variation in, electron density on the various phosphoryl oxygen atoms. ( 8 ) G. F. Svatos and J. Goldenson, Pittsburgh Conference on Acknow1edgment.-The authors wish to thank Analytical Chemistry and Applied Spectroscopy, February 27-March Corporal Robert Gelberg for technical assistance. 2, 1956.
COMMUNICATIONS TO THE EDITOR MAGNETIC PROPERTIES OF ZINC SULFIDE PHOSPHORS WITH MANGANESE ACTIVATOR Sir: Investigations have been carried out from 77 to 300°K. on the magnetic properties of unexcited cubic ZnS :Mn phosphors, prepared mainly with chloride-activator, The phosphor preparative procedure and magnetic measuring technique have been described in a previous artic1e.l It was found in the present investigation that appreciable loss of manganese occurred through reaction with the chloride coactivator, with loss of MnC12 a t the crystallization temperatures used. Incorporated manganese was therefore determined by chemical (colorimetric) analysis in all of the samples measured.2 The results for cubic ZnS :Mn phosphors are summarized in Table I.
ganese in ZnS are in good agreement with those in ZnzSi04. The Weiss constants for manganese in sulfides are greater than for manganese in silicates, indicating that interaction probably occurs to a greater extent in the cubic zinc sulfide lattice than in the rhombohedral zinc orthosilicate lattice. Schneider and England4 have indicated that spinspin interaction occurs in ZnS :Mn phosphors, by paramagnetic resonance investigations. It would be of interest to investigate the magnetic properties of ZnS :Mn phosphors which contain quenching amounts of paramagnetic transition element poisons.6
TABLE I SUMMARY OF MAGNETIC EFFECTS:AMOUNTS IN COLUMNS 1 AND 3 ARE GIVENIN PERCENT.BY WEIGHT
(1053).
4
1 Mn Added
2 NaCl
3 Mn Found
Bohr Magnetons
5 Weiss Constant
0.1% 1.0 10.0 10.0
Yes Yes Yes No
0.08% 0.49 1.64 9.0
5.75 5.81 5.71 4.62
N O
RCA LABORATORIES RADIOCORPORATION OF AMERICA SIMON LARACH PRINCETON UNIVERSITY JOHNTWRKEVICH PRINCETON, NEWJERSEY RECEIVED OCTOBER18,1956 (4) E. E. Schneider and T. 9. England, Phyeica, 17,221 (1951). ( 5 ) R. H. Bube, 8. Laraoh and R. E. Sbrader, P h y s . Rev., 92, 1135
T H E KINETICS OF NUCLEATION I N TURBULENT JETS
Sir: The rapid mixing which occurs when a turbulent 13.8 jet of vapor issues into a relatively stationary cooler 28.3 gas provides a means of quenching for studies of 93.0 the kinetics of nucleation. An analysis of the rate In comparing the properties of manganese in an of production of condensation nuclei in such a sysoxygen-dominated latticea with the sulfur-domi- tem enables a comparison of experimentally obnated lattice, it is found that the moments of man- served rates with theory. Figure 1 is a cross-section of a turbulent jet. The (1) s. Larach and J. Turkevich, Phys. Rev., 98, 1015 (1955). region in which mixing occurs may be characterized (2) Analyses b y Dr. M. C. Gardels. by n, the mass ratio of cooling gas to nozzle gas in a (3) S. Larach and , I . Turkevich, Phys. Reu., 89, 1000 (1953).
