Paramagnetic moments

The density of states at the Fermi-level N(pp) is responsible for many electronic properties, e.g. the electronic contribution to the low-temperature specific heat of a solid, and the Pauli paramagnetic moment of conduction electrons. The specific heat contribution may be written as ... 

Table 4. Nearest interatomic U-U spacings, effective paramagnetic moments, and estimated 7 eV XPS satellite intensities for various binary uranium compounds (from Ref. 122). The references for the intensities and distances are given in ...

It is now well known that many diamagnetic, square-planar nickel(II) chelates develop temperature-dependent paramagnetic moments in solution. The subject was last reviewed by Sacconi (221) in 1959, but later developments make a further summary worthwhile. 

Fig. 28. The magnetic susceptibility x versus temperature for various CeT2B2C compounds, indicating zero magnetic moment for the smaller T atoms Ni and Pd but finite paramagnetic moment for the larger T atoms Co,...

The next step is to connect the macroscopic susceptibility to individual molecular moments and finally to the number of unpaired electrons. From classical theory, the corrected or paramagnetic molar susceptibility is related to the permanent paramagnetic moment of a molecule, y. by ... 

As we know, this paramagnetic moment originates in the spins and orbital motions of the unpaired electrons in the substance. There are three possible modes of coupling between these components spin-spin, orbital-orbital, and spin-orbital. For some complexes, particularly those of the lanthanides, we must consider all three types of coupling. The theoretical paramagnetic moment for such a complex is given by... 

On the other hand, the product (sym. orb.) - (antisym. spin) is nondegenerate. A state that is nondegenerate in spin is called a spin singlet we have 2S + 1 = 1, and thus S = 0. A singlet state does not have a paramagnetic moment. 

Fig. 3. Mossbauer spectrum resulting from a magnetic liyperfine interaction between electron paramagnetic moment and Mossbauer nuclide nuclear magnetic moments...

It is important that the ordered moment at low temperature is considerably smaller (1.74 /Aij/lJ) than the effective paramagnetic moment, 3... 

The fact that the phase transition in UO2 has the first-order character and the ordered magnetic moment of 1.74 /ab is considerably lower than the paramagnetic moment (about 3 /ab) is qualitatively consistent with the ratio of the strength of the bilinear and biquadratic parts of the effective spin Hamiltonian (8) of the 5f2-5f2... 

TW is the relaxation rate for water protons in the absence of the metal ion, u is the paramagnetic moment of the ion and y and (i are conventional constants. We can now examine m.r.e. values in a series of complexes, in terms of p, and calculating r from known radii of ions. This will reveal changes in ts or/and x0/w. We commenced such a study using the Ln(III) complexes of dipicolinic acid. 

According to the Curie-Weiss law the theoretically predicted paramagnetic moment for a d d ferrimagnetic system should be around 4.90 pg rather than the observed Pe of 2.81 pg. However, the analysis of reported magnetic susceptibility data for a variety of ferrimagnetic double-perovskites [6,10-13] shows that the observed paramagnetic... 

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