Plutonium magnetic susceptibility

Fig. 3. Magnetic susceptibility of plutonium metal as a function of temperature where represent initially high density plutonium and , cast plutonium...

Magnetic Susceptibilities. The magnetic susceptibilities of both plutonium compounds (Figure 3) show a weak Curie-Weiss paramagnetism for R, peff=0.87uB, 0=2.6°K9 and for P, Ueff=0.52jj]j,... 

The type of waste feed has an effect on separator performance. Results of treatment of different types of wastes have yielded considerable differences in separation efficiencies. These differences can be attributed to variations in magnetic susceptibilities of the host materials and physical attachment of the plutonium to the residue. 

Results from magnetic susceptibility studies have been reported (50—53). Measurements (50) obtained by the Gouy method are shown in Figure 3. These are lower than those of other investigators. However, the temperature dependences of the magnetic susceptibilities, %, for the various plutonium allotropes were similar. a-Plutonium single crystals show a slight anisotropy of % (54). 

Sufficient einsteinium, produced through intense neutron bombardments of plutonium-239 in a reactor, was not available until 1961 to allow separation of a macroscopic amount. Cunningham. Wallmann. L. Phillips, and Gatti worked with submicrogram quantities to separate a small fraction nl pure einsteinium-235 compound and measure its magnetic susceptibility. Only a lew hundredths of a micrograni were available at that lime. 

It appears that the plutonium moment is heavily quenched by hybridization. This effect was found earlier in PuC samples as a function of the sample quality. In section 2.2.2 we will see that it occurs in many substances. As a matter of fact, PuN shows exactly the same features as NpTe. Finally, the need to analyze the susceptibility curves with an additional parameter, Xo, often indicates a questionable sample quality. In our opinion, the magnetic properties of PuN are not yet convincingly explained. The possibility that PuN shows the same features as the Pu chalcogenides (see below) cannot be excluded. This would give a logical explanation for the high value of Xo (half the actually measured susceptibility value) which is needed to construct a Curie-Weiss law in a limited temperature range. 

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