Butterfly M<sub>2</sub><sup>III</sup>Er<sub>2</sub> (M<sup>III</sup> = Fe and Al) SMMs: Synthesis, Characterization,
and Magnetic Properties
Yan Peng
Valeriu Mereacre
Christopher E. Anson
Annie K. Powell
10.1021/acsomega.8b00550.s002
https://acs.figshare.com/articles/dataset/Butterfly_M_sub_2_sub_sup_III_sup_Er_sub_2_sub_M_sup_III_sup_Fe_and_Al_SMMs_Synthesis_Characterization_and_Magnetic_Properties/6509480
The
reaction of <i>N</i>-(2-pyridylmethyl)iminodiethanol
(H<sub>2</sub>L, pmide), FeCl<sub>2</sub>·4H<sub>2</sub>O or
AlCl<sub>3</sub>·6H<sub>2</sub>O with ErCl<sub>3</sub>·6H<sub>2</sub>O and <i>p</i>-Me-PhCO<sub>2</sub>H in the ratio
of 2:1:1:4 in the presence of Et<sub>3</sub>N in MeOH and MeCN yielded
compounds [Fe<sub>2</sub>Er<sub>2</sub>(μ<sub>3</sub>-OH)<sub>2</sub>(pmide)<sub>2</sub>(<i>p</i>-Me-PhCO<sub>2</sub>)<sub>6</sub>]·2MeCN (<b>1</b>) and [Al<sub>2</sub>Er<sub>2</sub>(μ<sub>3</sub>-OH)<sub>2</sub>(pmide)<sub>2</sub>(<i>p</i>-Me-PhCO<sub>2</sub>)<sub>6</sub>]·2MeCN (<b>2</b>). These two complexes are isostructural, possessing a planar butterfly
motif with the Er<sup>III</sup> ions in the wingtip positions. Both
compounds show single molecule magnet (SMM) behavior. For the [Al<sub>2</sub>Er<sub>2</sub>] compound, the slow relaxation of the magnetization
under zero applied direct current (dc) field does not show maxima,
but the relaxation processes could be analyzed using an applied dc
field of 1000 Oe. In-depth alternating current measurements under
different dc fields on the [Fe<sub>2</sub>Er<sub>2</sub>] compound
reveals that the Fe–Fe and Fe–Er interactions speed
up the relaxation and decrease the energy barrier height of the SMM
in comparison with the [Al<sub>2</sub>Er<sub>2</sub>] case.
2018-06-13 13:31:09
dc
compound
OH
MeCN
Me-PhCO 2 H
relaxation
SMM
H 2 L
energy barrier height
Fe 2 Er 2
pmide
Et 3 N
Butterfly M 2 III Er 2
Al 2 Er 2
Me-PhCO 2
Er III ions