Pauling-Slater curve

Figure 1. The Slater-Pauling curve displaying saturation ferromagnetic moment for the first-row transition metal alloys. This figure shows a comparison of experimental values (solid curves) and predicted values (dashed lines) of the saturation ferromagnetic moment per atom, in Bohr magnetons, for Fe-Co, Co-Ni, and Ni-Cu alloys. The short vertical lines indicate change in crystal structure. When the Zener contribution is taken into account, the slope of the dashed line from Fe72Co28 to Ni44Cus6 changes from -1, as...

In order for unsynchronous resonance to occur, the atoms M+ and M° must have an unoccupied orbital available so that they can accept an additional bond. M does not require such an unoccupied orbital because the electroneutrality principle rules out its accepting an additional bond, which would convert it to M2. Accordingly, the structural requirement for a system to possess metallic character is that the fraction of the atoms M+ and M° have available an unoccupied orbital, called the metallic orbital. The average value of 0.72 orbital per atom for the metallic orbital, as deduced from the Slater-Pauling curve, implies that, with unsynchronous resonance of the covalent bonds, the metal consists of 28% M+, 44% M°, and 28% M. ... 

From the Slater-Pauling curve for the saturation magnetic moment of the first-row transition metal alloys (Figure 1), it was found empirically that the number of metallic orbitals per atom has the value 0.72, corresponding to 28% M+, 44% M°, and 28% M-. Based on the statistical treatment discussed in the preceding section, it is now possible to deduce this value on purely theoretical grounds [36]. 

The simultaneous solution of eqns. (24) and (25) for oj yields a = 0.444 and oj = 0.722. The former value is in excellent agreement with the observed composition Ni44Cu56 at the foot of the Slater-Pauling curve, and the latter value is essentially the same as the empirically deduced value of 0.72 for the average number of metallic orbitals per atom. 

Fig. 6.3. Slater-Pauling curve magnetic moment per atom as a function of the number of 3d + 4s electrons. (Adapted from Chikazumi, 1964.)...

Fig. 33. (0 Lattice parameters a (upper curve) and c (lower curve), (ii) Curie points, (iii) saturation magnetic moments at RT (solid circles) and LN2 (open circles), and (iv) anisotropy fields N (symbols as in iii) versus Co concentration in YFeio, Co,V2 alloys. The occurrence of maxima in 7 c(x) and A/,(x) plots can be explained, as for the Slater-Pauling curve, in terms of the rigid band model in which holes are present in both 3 subbands in the Fe-rich samples. (Jurczyk and Chistyakov 1989.)...

Fig. 14.92. The Curie temperatures and spontaneous moments of Y2(Fe, Co)n and Y2(Co, Ni)i7 as a function of electron concentration. Note the resemblance to the Slater-Pauling curve (fig. 14.67). (Taylor and Poldy, 1975).

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