论文信息 - Valence transition of samarium in hexaboride solid solutions Sm 1-xMxB6 (M = Yb 2+ , Sr2+ , La3+ , Y3+ , Th4+ )

Valence transition of samarium in hexaboride solid solutions Sm 1-xMxB6 (M = Yb 2+ , Sr2+ , La3+ , Y3+ , Th4+ )

The X-ray absorption measurements at the LIII edge have been carried out at 300 K in the solid solutions Sm1-xMxB 6 (M = Yb2+, Sr2+, La3+, Y3+, Th4+). The fine structure of the edge indicates that the average samarium valence tends towards Sm3+ with increasing Yb2+ and Sr2+ contents whereas the substitutions with La 3+, Y3+ and Th4+ involve a decrease of the average samarium valence reaching Sm2+ as x increases. The entire results obtained agree well with those deduced from the analysis of the cubic lattice parameter variation and from the magnetic susceptibility measurements.

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