Sb substituted Sm 2Fe 17-x Sb x materials have been synthesized by using modified reduction diffusion process with superfine Fe metal powder as a starting material. This synthetic route is unique and particularly usef...
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Sb substituted Sm 2Fe 17-x Sb x materials have been synthesized by using modified reduction diffusion process with superfine Fe metal powder as a starting material. This synthetic route is unique and particularly useful for the intermetallic compounds containing high volatile component. The substitution of Sb to the Sm 2Fe 17 significantly enhances the magnetic interaction between Fe atoms, which in turn, increases the Curie temperature of the materials. In addition, the chemical stability of Sm 2Fe 17 can also be improved by Sb substitution.
Magnetic coupling constants J for the complete structures of rare earth\|transition metal compounds:LGdCu(NO\-3)\-3·Me\-2CO(1,Gd(Ⅲ)Cu(Ⅱ)) and [Ce(C\-4H\-7ON)\-4(H\-2O)\-3][Cr(CN)\-6]·2H\-2O(2, Ce(Ⅲ)Cr(Ⅲ)...
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Magnetic coupling constants J for the complete structures of rare earth\|transition metal compounds:LGdCu(NO\-3)\-3·Me\-2CO(1,Gd(Ⅲ)Cu(Ⅱ)) and [Ce(C\-4H\-7ON)\-4(H\-2O)\-3][Cr(CN)\-6]·2H\-2O(2, Ce(Ⅲ)Cr(Ⅲ)) have been calculated by the combination of the broken\|symmetry approach with the spin project method under the DFT *** J value for 1 is a small number in absolute value -2 4cm -1 for calculation,3 5cm -1 for experimental *** spin density distributions are in detail discussed on the basis of Mulliken population analysis,taking into account the coexistence of spin delocalization and spin polarization *** 1,the spin distribution in the ground state may be understood as a result of the competition between two mechanisms:a spin delocalization from Cu(Ⅱ) and a spin polarization of Gd(Ⅲ),and the former is *** the case of 2,both transition metal Cr(Ⅲ) and rare earth Ce(Ⅲ) display a spin polarization effect on the surrounding atoms,where a counteraction of the opposite polarization effects leads a low spin density on the bridging ligand *** the ground state of 2,the stronger polarization effect of Cr(Ⅲ) even causes the positive spin density on the adjacent bridging atom N1.
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