TY - JOUR
T1 - Azido-cobalt(II) coordination polymers exhibiting slow magnetic relaxation and metamagnetic transition
AU - Mautner, Franz-Andreas
AU - Berger, Christian
AU - Fischer, Roland
AU - Massoud, Salah S.
AU - Speed, Saskia
AU - Vicente, Ramon.
PY - 2019/6/29
Y1 - 2019/6/29
N2 - Two coordination polymers of mono-dimensional doubly bridged-azido-cobalt(II) complexes catena-[Co(2,6-lutidine-N-oxide)(μ1,1-N3)2] (1) and catena-{[Co(μ1,1-N3)2(H2O)2](3-picoline-N-oxide)2} (2), where 2,6-lutidine-N-oxide = 2,6-dimethylpyridine-N-oxide and 3-picoline-N-oxide = 3-methylpyridine-N-oxide, were synthesized, and structurally characterized by single crystal X-ray crystallography. The Co(II) cations in complexes 1 and 2 are penta- and hexa-coordinate, respectively with four μ1,1-bridging azido groups and a terminal 2,6-lutidine-N-oxide molecule in 1 or two trans aqua molecules in 2. Magnetic relaxations in the zero field are consistent with single chain magnetic behavior (SCM) and the ac susceptibility measurements revealed that the weak ferromagnetic exchanges in the two complexes are associated with slow relaxation of magnetization. Complex 2 exhibits metamagnetic transition with an antiferromagnetic phase transition at 12 K at the applied field of 200 Oe.
AB - Two coordination polymers of mono-dimensional doubly bridged-azido-cobalt(II) complexes catena-[Co(2,6-lutidine-N-oxide)(μ1,1-N3)2] (1) and catena-{[Co(μ1,1-N3)2(H2O)2](3-picoline-N-oxide)2} (2), where 2,6-lutidine-N-oxide = 2,6-dimethylpyridine-N-oxide and 3-picoline-N-oxide = 3-methylpyridine-N-oxide, were synthesized, and structurally characterized by single crystal X-ray crystallography. The Co(II) cations in complexes 1 and 2 are penta- and hexa-coordinate, respectively with four μ1,1-bridging azido groups and a terminal 2,6-lutidine-N-oxide molecule in 1 or two trans aqua molecules in 2. Magnetic relaxations in the zero field are consistent with single chain magnetic behavior (SCM) and the ac susceptibility measurements revealed that the weak ferromagnetic exchanges in the two complexes are associated with slow relaxation of magnetization. Complex 2 exhibits metamagnetic transition with an antiferromagnetic phase transition at 12 K at the applied field of 200 Oe.
U2 - 10.1016/j.poly.2019.06.034
DO - 10.1016/j.poly.2019.06.034
M3 - Article
VL - 170
SP - 622
EP - 629
JO - Polyhedron
JF - Polyhedron
SN - 0277-5387
ER -