Slow magnetic relaxation in Co^II–Ln^III heterodinuclear complexes achieved through a functionalized nitronyl nitroxide biradical

Abstract

Five nitronyl nitroxide biradical-CoII–LnIII heterodinuclear complexes were achieved and the DyCo derivative displayed visible temperature/frequency-dependent χ′′ peaks, indicating the SMM behavior.

Regulating Spin Dynamics of Nitronyl Nitroxide Biradical Lanthanide Complexes through Introducing Different Transition Metals

“…The radical ligand NITPh-PyPzbis were synthesized according to the reported procedures. [19] Elemental analysis was tested using a Perkin-Elmer 240 elemental analyzer. FT-IR data were obtained on a Bruker Tensor 27 Spectrophotometer using KBr flakes.…”

“…All solvents and reagents were used as received without further purification. The radical ligand NITPh‐PyPzbis were synthesized according to the reported procedures [19] . Elemental analysis was tested using a Perkin‐Elmer 240 elemental analyzer.…”

“…[18] Very recently, our group utilized a functional nitronyl nitroxide biradical to achieve a family of biradical bridged CoÀ Ln complexes. [19] As an extension of our previous study, herein we synthesized a series of new biradical-Ln complexes with Mn or Ni ions, namely [LnM (hfac) 5 (NITPh-PyPzbis)] (M II = Mn II and Ln III = Gd 1, Dy 2, M II = Ni II and Ln III = Tb 3, Dy 4) to explore the effect of transition metals on the magnetic properties of the system. Magnetic studies show that complex 4 displays interesting two-step relaxations of magnetization indicating the SMM behavior while no such behavior is found in complexes 2 and 3.…”

“…Only less efforts have been paid to construct nitronyl nitroxide biradical‐based SMMs [18] . Very recently, our group utilized a functional nitronyl nitroxide biradical to achieve a family of biradical bridged Co−Ln complexes [19] . As an extension of our previous study, herein we synthesized a series of new biradical‐Ln complexes with Mn or Ni ions, namely [LnM(hfac) 5 (NITPh‐PyPzbis)] (M II =Mn II and Ln III =Gd 1 , Dy 2 , M II =Ni II and Ln III =Tb 3 , Dy 4 ) to explore the effect of transition metals on the magnetic properties of the system.…”

Synthesis, Crystal Structures and Magnetic Properties of Trinuclear {Ni2Ln} (LnIII = Dy, Ho) and {Ni2Y} Complexes with Schiff Base Ligands

“…Clearly this is not the case, as seen in Figure 8. Deviation from the Orbach process is often observed in 3d/4f heteronuclear complexes and has been attributed to the involvement of multiple relaxation mechanisms [39][40][41][42]. The temperature dependence of the relaxation time, τ, for 1 can be fitted with the Equation ( 2):…”