Autori: Benea D.; Isnard O.; Pop V.

Editorial: COMPUTATIONAL MATERIALS SCIENCE, 50, p.295, 2010.

Rezumat:

Detailed theoretical and experimental investigations of the electronic and magnetic properties of the Th(x)Y(1-x)Co(4)B compounds have been performed. The neutron powder diffraction shows that by Th for Y substitution, Th atoms occupy preferentially one (1a) of the two Y sites (1a and 1b). The preferential occupation on 1a and 1b crystal sites investigated by theoretical calculations is in good agreement with powder neutron diffraction results. The magnetic properties of the Th(x)Y(1-x)Co(4)B compounds are strongly influenced by the Th content x. The Curie temperature of the compound decreases with Th content from 380 K for YCo(4)B to 303 K for ThCo(4)B. The Th for Y substitution alter the magnetic coupling of the Co 2c atoms, which have the dominant contribution to the magnetization of the system. The magnetic moments behavior in the Th(x)Y(1-x)Co(4)B compounds is also related to the preferential occupation of crystallographic 1a and 1b sites by Th and Y atoms, respectively. The agreement between the calculated magnetic moments and the corresponding experimental results is discussed. All theoretical investigations of the electronic and magnetic properties of the system have been done using the Korringa-Kohn-Rostoker (KKR) band structure method in the ferromagnetic state. The substitutional disorder in the system has been accounted for by means of Coherent Potential Approximation (CPA).

Cuvinte cheie: Electronic band structure; Magnetic moments; Density of states