Transition metals magnetic properties

From a theoretical point of view, the 3d electrons and the 4f electrons independently show some important characteristics, such as the Kondo effect and heavy-fermion behavior. The properties of the electrons have been studied by many researchers. A theoretical analysis of the electrons, however, in a physical sense, is still insufficient for explaining the magnetic properties of lanthanide-transition-metal magnets. The difficulties mainly come from the complexity of the mixture of the 3d and 4f electrons and of the interactions among them in these materials. 

Many important conclusions of the calculations can be found in the original papers quoted. In the following sections, therefore, we will discuss a few interesting points concerning the effects of the third element on the magnetic properties of the lanthanide-transition-metal magnets. 

Small metal clusters are also of interest because of their importance in catalysis. Despite the fact that small clusters should consist of mostly surface atoms, measurement of the photon ionization threshold for Hg clusters suggest that a transition from van der Waals to metallic properties occurs in the range of 20-70 atoms per cluster [88] and near-bulk magnetic properties are expected for Ni, Pd, and Pt clusters of only 13 atoms [89] Theoretical calculations on Sin and other semiconductors predict that the stmcture reflects the bulk lattice for 1000 atoms but the bulk electronic wave functions are not obtained [90]. Bartell and co-workers [91] study beams of molecular clusters with electron dirfraction and molecular dynamics simulations and find new phases not observed in the bulk. Bulk models appear to be valid for their clusters of several thousand atoms (see Section IX-3). 

One of tire interesting aspects of transition-metal clusters is tlieir novel magnetic properties [91, 92, 93 and 94l]. ... 

Pastor G M, Dorantes-Davila J and Bennemann K H 1989 Size and structural dependence of the magnetic properties of small 3d-transition metal clusters Phys. Rev. B 40 7642... 

Compounds with Sc, Y, lanthanoids and actinoids are of three types. Those with composition ME have the (6-coordinated) NaCl structure, whereas M3E4 (and sometimes M4E3) adopt the body-centred thorium phosphide structure (Th3P4) with 8-coordinated M, and ME2 are like ThAsi in which each Th has 9 As neighbours. Most of these compounds are metallic and those of uranium are magnetically ordered. Full details of the structures and properties of the several hundred other transition metal-Group 15 element compounds fall outside the scope of this treatment, but three particularly important structure types should be mentioned because of their widespread occurrence and relation to other structure types, namely C0AS3,... 

INVESTIGATION OF GALVANO-MAGNETIC PROPERTIES OF TRANSITION METAL ALLOY SYSTEMS USING THE KUBO-GREENWOOD EQUATION... 

The magnetic properties of transition metal complexes. B. N. Figgis and J. Lewis, Prog. Inorg. 

The magnetic properties of polynuclear transition metal complexes. P. W. Ball, Coord. Chem. Rev., 1969, 4, 361-383 (150). 

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