Magnetic 3 d impurities in Nb and MO
نویسنده
چکیده
We calculate the electronic structure of 3d impurities in niobium and molybdenum. Our calculations rely on the local density approximation of density functional theory. Assuming a muffin-tin description of the atomic potentials, the impurity potential and the ones of the nearest neighbours are calculated self-consistently while the embedding of this perturbed cluster into the host is described correctly by the KKR-Green function method. In molybdenum we find rather large local moments for Mn. Fe and C O impurities. Surprisingly, in niobium we also obtain similar large moments for Cr , Mn and F e impurities. Whereas the results for 3d impurities in MO agree very well with the experimental data. a serious disagreement exists for the niobium case which is not understood.
منابع مشابه
Local Magnetism of 3d and 4d Impurities in Ag and Pd Clusters
The local magnetic properties of Ag12TM and Pd12TM clusters with Ih symmetry (TM = Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Y, Zr, Nb, Mo, Tc, Ru, Rh, and Pd have been systematically studied with the density functional formalism, and the Kohn-Sham equation is solved self-consistently with the discrete variational method (DVM). A special attention is paid to the comparisons of local magnetism for impuriti...
متن کاملCombined effects of pressure, temperature, and magnetic field on the ground state of donor impurities in a GaAs/AlGaAs quantum heterostructure
In the present work, the exact diagonalization method had been implemented to calculate the ground state energy of shallow donor impurity located at finite distance along the growth axis in GaAs/AlGaAs heterostructure in the presence of a magnetic field taken to be along z direction. The impurity binding energy of the ground state had been calculated as a function of confining frequency and mag...
متن کاملActivation and cleavage of dinitrogen by three-coordinate metal complexes involving Mo(III) and Nb(II/III).
Density functional calculations have been employed to rationalize why the heteronuclear N(2)-bridged Mo(III)Nb(III) dimer, [Ar((t)Bu)N](3)Mo(mu-N(2))Nb[N((i)Pr)Ar](3)(Ar = 3,5-C(6)H(3)Me(2)), does not undergo cleavage of the dinitrogen bridge in contrast to the analogous Mo(III)Mo(III) complex which, although having a less activated N-N bond, undergoes spontaneous dinitrogen cleavage at room te...
متن کاملFirst observation of a fully magnetic 4d impurity on the surface of Au
– We observe for the first time a fully magnetic 4d surface impurity on the surface of a noble metal. Au films are covered with 1/100 of a monolayer of Mo. The Mo atoms cause a dephasing of the conduction electron coherence which is of the same order of magnitude as the dephasing by magnetic Fe atoms. The dephasing is measured by weak localization and proves the strong magnetic character of the...
متن کاملElectronic structures of defects and magnetic impurities in MoS2 monolayers
We provide a systematic and theoretical study of the electronic properties of a large number of impurities, vacancies, and adatoms in monolayer MoS2, including groups III and IV dopants, as well as magnetic transition metal atoms such as Mn, Fe, Co, V, Nb, and Ta. By using density functional theory over a 5 × 5 atomic cell, we identify the most promising element candidates for p-doping of MoS2....
متن کامل