ic9b00946_si_001.pdf (862.55 kB)
A Ferromagnetically Coupled, Bell-Shaped [Ni4Gd5] Cage
journal contribution
posted on 2019-08-14, 21:03 authored by Foteini E. Kakaroni, Demetrios I. Tzimopoulos, Hector W. L. Fraser, Milosz Siczek, Tadeusz Lis, Marco Evangelisti, Euan K. Brechin, Constantinos J. MiliosReaction
between NiCl2·6H2O, 2-hydroxy-4-methyl-6-phenyl-pyridine-3-amidoxime
(H2L), benzoic acid, and M(NO3)3·6H2O (M = Gd, Y) in MeCN under basic conditions yields the complexes
[NiII4GdIII5(PhCOO)10(HL)4(HLzw)4(OH)2(NO3)2]Cl·13.6MeCN·H2O
(1·13.6MeCN·H2O) and [NiII4YIII5(PhCOO)10(HL)4(HLzw)4(OH)2(NO3)1.5(H2O)0.5]0.5Cl(NO3)·3H2O (2·3H2O). Both
clusters display similar structures, consisting of a bell-shaped {NiII4MIII5} unit, in which a
linear “zigzag” {Ni4} subunit bisects the
central {MIII5} “ring”. Direct
(dc) and alternating current (ac) magnetic susceptibility measurements
carried out in the 2–300 K temperature range for complexes 1 and 2 revealed ferromagnetic intermolecular
interactions, while heat-capacity measurements for the Gd analogue
suggest that complex 1 lowers its temperature from T = 9.6 K down to 2.3 K by adiabatically demagnetizing from Bi = 7 T to Bf = 0.