Pauli spin paramagnetism

The absence of localized states is clearly supported by the small, Pauli-type paramagnetism of Lal2, 0 db 5 and (30 dz 10) X 10 e.m.u. mole at 299° and 78°K., respectively. Values of this magnitude are characteristic of metals where they are (ideally) associated with the Pauli spin paramagnetism of the conduction electrons. In the present case the results of correction for the diamagnetic contribution of the iodide ions in LaL [ (104 dz 5) and (134 dz 10) X 10 , respectively] are again remarkably (and probably fortuitously) close to those for the metal (113 and 139 X 10" ) (22). 

The minimum energy gap is also the important factor for other properties of a solid which depend on the electrons in the conduction band. These include the Pauli spin paramagnetism, and the (small) contribution of the electrons to thermal conductivity. All of these properties are due to extremely small concentrations of free electrons. Thus for silicon, where El = 1.1 eV, the number of conduction electrons is only 2 x 10 /cm, compared with an atom concentration of 5 X 10 /cm. This is for a sample where impurity concentrations have been reduced to 1 part in 10 by zone refining. 

The magnetic susceptibility Xmoi ScSe as measured in He or vacuum (--0.05 Pa) and corrected for the diamagnetism of the ionic cores Increases linearly from 70x 10 cm /molat 300 K to ca. 77 X 10" cm /mol at 700 K. The susceptibility of ScSe is independent of the magnetic induction, studied in fields ranging from 0.7 to 1.4 T. True paramagnetic susceptibility, Pauli spin paramagnetism of the conduction electrons, and the Van Vleck polarization paramagnetism are discussed in the paper, Adamyan et al. [6]. 

Fig. 4. Spin paramagnetism of metal dusters with odd (1) and even (2) numbers of dectrons. As the spin-orbital interaction increases, the spin paramagnetism behavior approaches normal Pauly paramagnetism [11]...

Pauli paramagnetism + 10 Independent None Spin and orbital motion of delocalised electrons... 

Takeda, 1983) shows that Fe in this oxide is in the high-spin state down to 4K. CaFeOj, on the other hand, shows disproportionation of Fe to Fe and Fe below 290 K. In the last but one column containing S = j cations, metallic and Pauli paramagnetic LaNiOj should be separated from antiferromagnetic YNiOj and LuNiOj, indicating that in LaNiOj b > b and in YNiOj b < b . Similarly, LaCoOj should be separated from LaRhOj because the latter is a narrow gap semiconductor with a filled t2g n ) band and an empty eg a ) band. 

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