Observation of an unusual field dependent slow magnetic relaxation and two distinct transitions in a family of new complexes
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چکیده
An unusual field dependent slow magnetic relaxation and two distinct transitions were observed in a family of new rare earth-transition metal complexes, [Ln (bipy) (H2O)4 M(CN)6] ·1.5 (bipy) · 4H2O (bipy = 2,2’-bipyridine; Ln = Gd,Y; M = Fe, Co). The novel magnetic relaxation, which is quite different from those in normal spin glasses and superparamagnets but very resembles qualitatively those in single-molecule magnet Mn12-Ac even if they possess different structures, might be attributed to the presence of frustration that is incrementally unveiled by the external magnetic field. The two distinct transitions in [GdFe] were presumed from DC and AC susceptibility as well as heat capacity measurements. PACS numbers: 75.50.Xx, 75.40.-s, 81.05.Zx Typeset using REVTEX
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تاریخ انتشار 2001