Magnets transition metal borides

Because they exhibit interplay of magnetic and superconducting properties, the formation and crystal chemistry of MRgMy4B4 compounds have been examined. Ternary rare-earth and actinide (Th, U, Pu)-transition metal borides of the approxi-... 

Later developments of linear methods have been in the direction of self-consistent calculations of ground-state properties utilising local spin-density-functional formalism [1.51,52] for exchange and correlation. The basis of the self-consistency procedure was given in papers by Madsen et al. [1.53], Vouisen et al. [1.54] and Andersen and Jepsen [1.55], and was soon followed by results for the magnetic transition metals [1.56], the noble metals [1.57], some lanthanides [1.58], the actinides [1.59,60], and the 3d transition metal monoxides [1.61,62]. In this context one should also mention calculations of the electronic structure in transition metal compounds [1.63,64], A15 compounds [1.65,66], rare-earth borides [1.67], Chevrel... 

Nanomaterials of various transition metal borides, carbides and silicides with diverse magnetic and conducting properties have been obtained from 1 and other diacetylene-containing carboranylenesiloxanes using the same strategy as used in the P -MOjC formation. Some of the nanomaterials produced include CoB, FeCoB, CuBj, and Fe Sij. 

Others. There is a large body of work on the rare earth transition metal borides especially following the discovery of the excellent permanent magnet Nd2Fei4B described at the beginning of this Section 3.2.2, with the majority of investigations being focused on Tr = Fe and Co. ... 

Following the discoveries of the excellent magnetic properties of file rare earth transition metal borides, the rare earfli transition metal carbides have also been investigated extensively. For example, an early review and detailed comparative study have been given by Buschow. A more recent review on particular developments has been given for Sm-Fe-C systems, for example. ... 

While tile magnetic performances have not been found yet to exceed the best rare earth transition metal borides, the rare earth transition metal carbides also have variation in properties and are interesting systems to study. 

The rare earth borides, carbides, and nitrides aU have compounds that manifest superconductivity, fundamental magnetic transitions, and other interesting phenomena such as strongly correlated heavy fermion behavior. Some of the rare earth transition metal borocarbides such as RTr2B2C have shown fascinating properties where magnetism and superconductivity phenomena coexist. 

Quaternary boro-nitrides. The well-known magnetic properties of R2T14B ternary borides (T=transition metal) are typified by the neodymium iron compound Nd[2Fei4B, discovered in 1983. Several studies aimed at introducing interstitial nitrogen in the composition of such permanent-magnet materials in order to improve their characteristics, in particular the Curie temperature. 

Maple, M.B., H.C. Hamaker and L.D. Woolf, 1982, Superconductivity, magnetism and their mutual interaction in ternary rare earth rhodium borides and some ternary rare earth transition metal stannides, in Superconductivity in Ternary Compounds n. Topics in Current Physics, Vol. 34 (Springer, Berlin) pp. 99-141. 

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