A new ferrimagnetically ordered charge-transfer complex based on high-spin iron(III) chelate tetracyanoethenide with a Tc of 10 K
The reaction of the high-spin iron(II) quadridentate chelate complex [Fe(L)], (L=diethyl( E, E)-2,2′-[1,2-phenylenebis-(iminomethylidyne)]-bis-[3-oxobutanoate]), with the electron acceptor tetracyanoethylene (TCNE) leads to the formation of the 1:1 charge-transfer (CT) complex [Fe(L)] +[TCNE] −. The...
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Published in | Journal of magnetism and magnetic materials Vol. 246; no. 1; pp. 283 - 289 |
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Main Authors | , , |
Format | Journal Article |
Language | English |
Published |
Amsterdam
Elsevier B.V
01.04.2002
Elsevier Science |
Subjects | |
Online Access | Get full text |
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Summary: | The reaction of the high-spin iron(II) quadridentate chelate complex [Fe(L)], (L=diethyl(
E,
E)-2,2′-[1,2-phenylenebis-(iminomethylidyne)]-bis-[3-oxobutanoate]), with the electron acceptor tetracyanoethylene (TCNE) leads to the formation of the 1:1 charge-transfer (CT) complex [Fe(L)]
+[TCNE]
−. The magnetic characterisation of the CT salt indicates a chain structure with alternating
S=
5
2
high-spin iron(III) and
S=
1
2
TCNE
− radicals in which the spin centres are antiferromagnetic correlated. The antiferromagnetic intrachain interaction parameter is very weak (
J
intra≈−8
cm
−1) based on the spin Hamiltonian
H=−J
intra
S
i
S
j
. At
T=2
K and
H=5.5
kG the magnetisation for the CT complex is about 83% of the saturation magnetisation value expected for a
S
total
=(
5
2
−
1
2
)=2
system. A magnetic hysteresis loop was observed at
T=2
K with a coercive field of 200
G. Below 10
K, the complex shows a weak spontaneous magnetisation characteristic for a canted ferrimagnet. |
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ISSN: | 0304-8853 |
DOI: | 10.1016/S0304-8853(02)00075-6 |