Two 3d-4f double helical chains including [Dy2M2]: N (M = NiII and CoII) cores exhibiting slow magnetic relaxation

Article abstract of DOI:10.1039/c6dt00951d

Two new 3d-4f heterometallic 1D chains of formulae {[Dy₂M₂L₄(NO₃)(H₂O)₃][Dy₂M₂L₄(NO₃)(CH₃COO)(H₂O)₂]·NO₃

Full text of DOI:10.1039/c6dt00951d

View Article Online
View Journal
Dalton
Transactions
Accepted Manuscript
This article can be cited before page numbers have been issued, to do this please use: S. She, Y. Li and
W. Li, Dalton Trans., 2016, DOI: 10.1039/C6DT00951D.
This is an Accepted Manuscript, which has been through the
Royal Society of Chemistry peer review process and has been
accepted for publication.
Accepted Manuscripts are published online shortly after
acceptance, before technical editing, formatting and proof reading.
Using this free service, authors can make their results available
to the community, in citable form, before we publish the edited
article. We will replace this Accepted Manuscript with the edited
and formatted Advance Article as soon as it is available.
You can find more information about Accepted Manuscripts in the
Information for Authors.
Please note that technical editing may introduce minor changes
to the text and/or graphics, which may alter content. The journal’s
standard Terms & Conditions and the Ethical guidelines still
apply. In no event shall the Royal Society of Chemistry be held
responsible for any errors or omissions in this Accepted Manuscript
or any consequences arising from the use of any information it
contains.
www.rsc.org/dalton

View Article Online
DOI: 10.1039/C6DT00951D
Page 1 of 7
Dalton Transactions
Journal Name
RSCPublishing
ARTICLE
Two 3d-4f double helical chains including [Dy2M2]n (M
= NiII and CoII) cores exhibiting slow magnetic
relaxation
Cite this: DOI: 10.1039/x0xx00000x
Shixiong She,a Yahong Li*a and Wu Lib
Received 00th January 2012,
Accepted 00th January 2012
Two
{[Dy2M2L4(NO3)(H2O)3][Dy2M2L4(NO3)(CH3COO)(H2O)2]∙NO3∙12H2O∙2C2H5OH}n [M = Ni
); Co )] have been prepared using the multidentate ligand 2-{[(2-hydroxy-3-
new
3d-4f
heterometallic
1D
chains
of
formulas
(
1
(2
DOI: 10.1039/x0xx00000x
methoxyphenyl)methylidene]amino}benzoic acid (H2L), which has NO and OO’ chelating
pockets that are able to selectively encapsulate LnIII and transition metal ions, respectively.
Crystal structure analyses reveal that two complexes are isostructural and display one-
dimensional ladder-like double helical chain structures, in which the two single helical chains
www.rsc.org/
{[Dy2M2L4(NO3)(H2O)3]+} and {Dy2M2L4(NO3)(CH3COO)(H2O)2} (M = Ni(
run along c-axis and have opposite chirality. Complexes and represent the first example of
1), Co(2)) both
1
2
3d-4f double-chain frameworks in which the compositions of the two individual chains are
different. Variable temperature dc magnetic susceptibility studies reveal different strength of
ferromagnetic interactions between magnetic centers in
1 and 2, which is mainly attributed to
the different metal centers and finally result in the distinctive magnetic dynamic behaviors.
Introduction
anisotropy;10 TbIII and DyIII ions have commonly been employed
because they possess intrinsic high-spin and strong Ising-type
Molecular magnetic materials, including single molecule magnets
(SMMs) and single-chain magnets (SCMs), have received
enormous attention over the past decades due to their potential
applications in quantum computations, high-density data storage
and molecular spintronics.1,2 During early researches on SMMs, a
large number of complexes based on 3d metal ions were
synthesized in order to achieve large effective barrier (Ueff).3
Despite of extremely large spin values, some complexes did not
behave as SMMs due to the lack of Ising-type magnetic anisotropy,
suggesting that single ion anisotropy is the crucial factor for
designing SMMs.4 After the first discovery of lanthanide-SMM (4f-
SMM) in 2003 with an energy barrier of Ueff = 230 K,5 a plethora
of pure 4f-SMMs have been obtained,6 due to the large total
angular moment (J) and single-ion anisotropy of 4f metal ions.7
However, there are two major obstacles to construct 4f-SMMs with
superior magnetic properties, including the quantum tunneling that
lowers the effective relaxation energy barrier and very weak
interactions between Ln3+ ions which result in lower spin ground
state than that for a single ion.8
It has been reported that the merge of 3d metal ions with 4f spin
carriers would be a promising strategy to assemble SMMs, since
the intermediate magnetic exchange between 3d and 4f ions may
effectively reduce quantum tunneling of the magnetization (QTM)
and result in longer relaxation times.9
Up to now, many 3d-4f heterometallic complexes have been
synthesized. In these complexes, 3d ions such as CoII, NiII, MnIII
and FeIII have been chosen due to their stronger magnetic
anisotropy, therefore fulfilling the requirements of slow relaxation
of the magnetization.11 However, due to the specific chemical
natures of 3d and 4f ions, the synthetic approaches that could
rationally integrate 3d and 4f ions into one system are still less
developed. The synthetic challenge involves discovering a suitable
ligand which could incorporate different metal ions into a single
molecular entity or a 1D chain system, giving heterometallic
complexes with interesting topologies and magnetic properties.
Different kinds of organic ligands, e.g., oximes,12 amino acids,13
aminopolyalcohols,14 Schiff bases,9 etc., have been used to produce
new types of 3d-4f compounds.
In the present work, we have used 2-{[(2-hydroxy-3-
methoxyphenyl)methylidene]amino}benzoic acid (H2L)15 for the
synthesis of DyIII-NiII and DyIII-CoII 1D chain complexes. By
introducing carboxyl and hydroxyl groups into the ligand, H2L has
NO and OO’ coordination pockets with preference for transition
metal ions and LnIII ions. Meanwhile, it has been shown that the
exchange interaction between DyIII and NiII in DyIII-NiII
compounds is ferromagnetic.16 Two new heterometallic complexes
of formulas {[Dy2M2L4(NO3)(H2O)3][Dy2M2L4(NO3)(CH3COO)
(H2O)2]∙NO3∙12H2O∙2C2H5OH}n [M = Ni (1); Co (2)] were
isolated by the reactions of H2L, Dy(NO3)3·6H2O, and
Ni(CH3COO)2·4H2O (or Co(CH3COO)2·4H2O) under the
solvothermal conditions. Their syntheses, structures, and magnetic
properties are described in detail in this paper.
This journal is © The Royal Society of Chemistry 2013
J. Name., 2013, 00, 1-3 | 1

View Article Online
Dalton Transactions
DOI: 10.1039/C6DT00P95a1gDe 2 of 7
ARTICLE
Journal Name
The X-ray diffraction analysis indicates they both crystallize in the
Experimental section
tetragonal system with the space group I41. As the two complexes
are isostructural, complex 1 is chosen to depict the structure in
detail. Complex 1 consists of two single-helical chains of formulas
All solvents and reagents were obtained from commercial sources
and used as received without further purification. The Schiff base
ligand (H2L) was prepared by a condensation reaction between o-
vanillin and 2-aminobenzoic acid in 1:1 molar ratio in methanol.15
{[Dy2Ni2L4(NO3)(H2O)3]+}
and
{Dy2Ni2L4(NO3)(CH3COO)
(H2O)2}, one nitrate ion as counterion to compensate the charge of
the {[Dy2Ni2L4(NO3)(H2O)3]+} chain, 12 solvent water molecules
and 2 solvent ethanol molecules. The compositions of the two
chains are different. As shown in Fig. 1, in the chain of
{[Dy2Ni2L4(NO3)(H2O)3]+}, the asymmetric unit consists of two
Syntheses of complexes
{[Dy2Ni2L4(NO3)(H2O)3][Dy2Ni2L4(NO3)(CH3COO)(H2O)2]∙NO3
∙12H2O∙2C2H5OH}n (1). A mixture of Dy(NO3)3·6H2O (0.054 g,
0.12 mmol), Ni(CH3COO)2·4H2O (0.024 g, 0.12 mmol), H2L
(0.020 g, 0.075 mmol) was dissolved into ethanol (4 mL) and water
(4 mL), and then this solution was sealed in a glass tube. The tube
was heated at 75 °C for 2 days. After cooling to room temperature,
red crystals of 1 were obtained in 35% yield based on Dy.
Elemental analysis (%) calcd for C126H137Ni4Dy4N11O62: C, 41.10;
H, 3.75; N, 4.18. Found C, 38.23; H, 3.75; N, 4.02. Selected IR
data (KBr, cm−1): 3404 s, 1620 s, 1597 s, 1544 s, 1470 s, 1384 s,
1298 m, 1235 s, 1195 s, 1095 s, 966 m, 853 w, 769 w, 741 m, 709
w, 642 w, 539 w.
-
DyIII ions, two NiII ions, four L2- ligands, one NO3 ion and three
water molecules. The coordination environments of the two NiII
ions are identical (Fig. S1). Each NiII ion possesses a slightly
elongated octahedral geometry, in which the equatorial plane is
formed by N2O2 atoms from two L2- ligands and the two axial
positions are occupied by two carboxylate oxygen atoms from the
same L2- ligands. The axial bond lengths (Ni-O 2.082-2.097 Å) are
relatively longer than the equatorial ones (Ni-O/N 2.016-2.034 Å).
The coordination environments of Dy1 and Dy2 ions in the chain
of {[Dy2Ni2L4(NO3)(H2O)3]+} are different. The Dy1 center has the
{DyO9} coordination environment which is comprised of two
phenolate oxygen atoms, two methoxy oxygen atoms and one
carboxylate oxygen atom from three L2- ligands, two oxygen atoms
from one chelating nitrate anion, and two oxygen atoms from two
water molecules. The Dy2 center is eight coordinated with a {DyO8}
environment, with two phenolate oxygen atoms, two methoxy
oxygen atoms and one carboxylato oxygen atom being from three
L2- ligands, and three oxygen atoms being from three water
molecules. It is worth to note that the neighboring NiII and DyIII
ions are bridged by two modes. In the first mode, the metal ions are
doubly bridged by two phenolato oxygen (µ2-O) atoms from two
L2- ligands to form a DyNiO2 rhombus with angles in the range of
104.12(19)-108.36(19)°, 66.29(15)-66.89(16)° and 78.09(17)-
79.00(18)° for Dy-O-Ni, O-Dy-O and O-Ni-O, respectively. The
distances are 3.5013(10) Å for Dy1-Ni1, and 3.4986(11) Å for
Dy2-Ni2. In the other mode, two carboxylate ions belonging to two
L2- ligands and displaying a μ2-η1:η1 bridging mode link two pairs
of DyIII and NiII ions. The distances are 5.8528(15) Å for Dy1-Ni2,
and 6.1546(16) Å for Dy2-Ni1. Thus, the two DyIII ions and two
NiII ions are connected together to give a [Dy2Ni2] unit. The
adjacent [Dy2Ni2] units are further connected by two carboxylate
oxygen atoms of two L2- ligands to generate a ladder-like single-
helical chain along c-axis, with a pitch of 22.9224 Å based on the
repeat unit of two [Dy2Ni2] moieties and two connecting
carboxylate groups.
{[Dy2Co2L4(NO3)(H2O)3][Dy2Co2L4(NO3)(CH3COO)(H2O)2]∙N
O3∙12H2O∙2C2H5OH}n (2). Complex 2 was obtained by the same
procedure as that of 1, using Co(CH3COO)2·4H2O in place of
Ni(CH3COO)2·4H2O. Yield of 2 is 41% based on Dy. Elemental
analysis (%) calcd for C126H137Co4Dy4N11O62: C, 41.09; H, 3.75; N,
4.18. Found C, 38.01; H, 3.78; N, 3.96. Selected IR data (KBr,
cm−1): 3373 s, 2972 m, 1619 s, 1597 s, 1582 m, 1540 s, 1470 m,
1456 m, 1385 s, 1298 m, 1235 s, 1194 s, 1094 s, 1049 s, 969 m,
879 m, 767 w, 738 m, 710 w, 640 w, 537 w.
X-ray diffraction crystallography
Data were collected at room temperature on Bruker Smart ApexII
diffractometer equipped with a graphite monochromator utilizing
Mo Kα radiation; the ω-2θ scan technique was applied. The
structures were solved by direct methods using SHELXS-97and
refined on F2 using full-matrix least-squares with SHELXL-97.17 In
addition to the refined lattice solvents the crystal structures
contained significant pores (8430 and 7870 Å3 for 1 and 2
respectively) containing the highly disordered solvents that could
not be satisfactorily refined. The SQUEEZE routine of PLATON
was used in the treatment of the crystallographic data. Some lattice
solvents may have been rapidly lost once crystals were removed
from the mother liquor, and SQUEEZE may not always give a
completely accurate determination of residual electrons. Despite
the difficulty in crystallographically determining the lattice
solvents, the composition and connectivity of complexes 1 and 2
are unambiguous. The refinement details for the new complexes
reported in this work are summarized in Table 1. See CIF files for
further details.
Results and discussion
Descriptions of structures
2 | J. Name., 2012, 00, 1-3
This journal is © The Royal Society of Chemistry 2012

View Article Online
DOI: 10.1039/C6DT00951D
Page 3 of 7
Journal Name
Dalton Transactions
ARTICLE
Table 1 Crystal data and structure refinement for complexes 1 and 2
chain frameworks in which the compositions of the two individual
chains are different, demonstrating the novelty of this work.
1
2
Empirical formula
Formula weight
Temperature/K
Crystal system
Space group
a/Å
C126H137Dy4 Ni4N11O62
3682.27
291(2)
tetragonal
I41
26.2770(12)
44.4110(15)
30665(3)
8
1.595
2.495
C126H137Co4Dy4N11O62
3683.24
291(2)
tetragonal
I41
26.2860(12)
44.3921(15)
30673(3)
8
1.595
2.436
c/Å
Volume/Å3
Z
ρcalc g/cm3
μ/mm-1
F(000)
14736.0
0.290 × 0.150 × 0.130
MoKα (λ = 0.71073)
14704.0
0.240 × 0.220 × 0.200
MoKα (λ = 0.71073)
Crystal size/mm3
Radiation
2θ range for data
collection/°
3.158 to 56.612
1.8 to 56.616
-33 ≤ h ≤ 34, -26 ≤ k ≤ -35 ≤ h ≤ 31, -28 ≤ k
Index ranges
34, -54 ≤ l ≤ 58
≤ 35, -59 ≤ l ≤ 59
Reflections collected
Independent
111960
112866
36977 [Rint = 0.0453, 37997 [Rint = 0.0273,
reflections
Rsigma = 0.0547]
36977/1/1713
1.005
Rsigma = 0.0558]
Data/restraints/param
eters
37997/2131/1753
Goodness-of-fit on F2
0.865
Final
[I>=2σ (I)]
R
indexes R1 = 0.0336, wR2
=
=
R1 = 0.0222, wR2
0.0451
R1 = 0.0348, wR2
0.0467
=
=
Fig. 1 Asymmetric units in the chains of {[Dy2Ni2L4(NO3)(H2O)3]+} and
{Dy2Ni2L4(NO3)(CH3COO)(H2O)2} in compound 1. Hydrogen atoms and
crystallization solvent molecules have been omitted for clarity.
0.0688
Final R indexes [all R1 = 0.0618, wR2
data]
0.0797
Largest
diff.
0.93/-0.75
0.533(6)
0.51/-0.30
0.400(4)
peak/hole / e Å-3
Flack parameter
(a)
In the chain of {Dy2Ni2L4(NO3)(CH3COO)(H2O)2}, the
asymmetric unit consists of two DyIII ions, two NiII ions, four L2-
ligands, one NO3 ion, one acetate ion and two water molecules.
-
The coordination spheres of two NiII ions are the same as those of
NiII ions in the chain of {[Dy2Ni2L4(NO3)(H2O)3]+}. The
coordination environment of Dy3 in the chain of
{Dy2Ni2L4(NO3)(CH3COO)(H2O)2} is the same as that of Dy1 in
the chain of {[Dy2Ni2L4(NO3)(H2O)3]+}, while the coordination
environment of Dy4 is different from that of Dy2. The Dy4 centre
is eight coordinated with a {DyO8} mode, with two phenolato
oxygen atoms, two methoxy oxygen atoms and one carboxylato
oxygen atom being from three L2- ligands, two oxygen atoms being
from water molecules and one oxygen atom being from the acetate
ion. The DyIII ions and NiII ions are alternatively connected by
phenolato oxygen atoms and carboxylate groups to form a [Dy2Ni2]
unit. The adjacent two [Dy2Ni2] units are linked by two carboxylate
groups to generate a ladder-like single-helical chain along c-axis,
(b)
with
a pitch of 23.1184 Å, slightly longer than that of
Fig. 2 (a) The structures of the chains of {[Dy2Ni2L4(NO3)(H2O)3]+} and
{Dy2Ni2L4(NO3)(CH3COO)(H2O)2} in 1. (b) The ladder-like shape and the
{[Dy2Ni2L4(NO3)(H2O)3]+} chain. The distances are 3.4978(10) Å
for Dy3-Ni3, 3.5037(11) Å for Dy4-Ni4, 5.7617(15) Å for Dy3-
Ni4 and 6.2197(16) Å for Dy4-Ni3, close to the corresponding
values in the chain of {[Dy2Ni2L4(NO3)(H2O)3]+}.
Ⅲ
Ⅱ
arrangements of Dy and Ni ions in 1.
The most fascinating feature of complex 1 is that two single
helical chains all run along c-axis with opposite chirality,
displaying an unusual “DNA”-shaped motif with ladder-like
double-chain structure (Fig. 2).
Complexes 1 and 2 are members of a small family of
heterometallic compounds with double-chain frameworks.18
However, complexes 1 and 2 are the first reported 3d-4f double-
Thermal studies of 1 and 2
Complexes 1 and 2 were studied by TG-DSC (Fig. S2, S3). It is
noticed that the crystals of the two complexes quickly lose solvent
molecules during the isolation process and turn opaque. As for 1,
the calculated mass loss corresponding to the solvent guests from
the crystals and all water molecules bound to the metal centers
This journal is © The Royal Society of Chemistry 2012
J. Name., 2012, 00, 1-3 | 3

View Article Online
Dalton Transactions
DOI: 10.1039/C6DT00P95a1gDe 4 of 7
ARTICLE
Journal Name
between 100 and 300°C is 10.81%. However, the experimental
result is 11.32%, this indicates that one water molecule (calc.
0.48%) from the mother liquor might be contained during the test
process. The TG analysis of 2 shows a mass loss of 10.90%
between 100 and 300°C , fully consistent with the calculated result
(calc. 10.80%). However, it also shows a 9.08% mass loss around
51.5°C , which could be attributed to remaining solvents coming
from the mother liquor.
Magnetic studies of 1 and 2
Variable-temperature magnetic measurements were performed with
polycrystalline samples of 1 at an applied magnetic field of 1 kOe
in the range of 2−300 K (Fig. 3). The MT value of 1 at room
temperature is 62.28 emu mol-1 K for two [Dy2Ni2] units, a value
which is as expected for four magnetically isolated DyIII ions and
four magnetically noninteracting NiII ions (g = 4/3, J = 15/2 for
Fig. 4 M vs H/T plots at different temperatures below 8 K for 1.
DyIII and g = 2, S = 1 for
NiII). Upon cooling, the MT value
gradually increases to 63.21 emu mol-1 K at 140 K, which probably
was ascribed to weak ferromagnetic interactions between the
paramagnetic centers. Then MT value further increases to a sharp
peak value of 69.15 emu mol-1 K at 4 K before decreasing again to
67.78 emu mol-1 K at 2 K, indicating ferromagnetic coupling
between paramagnetic centers.
The field dependence of the magnetization for complex 1 was
collected at 2, 3, 4, 5 and 8 K (Fig. 4). The magnetization revealed
nonsuperposition plots and similar rapid increase in the very low
field region, which eventually reaches the value of 51.42 Nβ at 2 K
and 7 T (Fig. S4), without saturation, suggesting the presence of
magnetic anisotropy and/or considerable crystal-field effects.19
To further understand the magnetism of 1, ac dynamic
susceptibility measurements were performed in the temperature
range 20-2 K at an oscillating 2.0 Oe field for variable frequencies
(from 999 to 32 Hz). Both in- and out-of-phase signals show
frequency dependence without peaks, suggesting a slow relaxation
behavior of the magnetization. This is consistent with the hysteresis
measurement in which no hysteresis displays at 2 K (Fig. 5, Fig.
S5). Since the maxima in the plots of '' versus T can not be
observed even up to 999 Hz, a dc field of 1 kOe were applied to the
system in ac measurements. An increase in '' with still no peak
shapes were obtained however, which can be attributed to the
presence of a fast relaxation of the magnetization through a
quantum tunneling mechanism.
Fig. 5 Left: temperature dependence of the in-phase ' and out-of-phase ''
at different frequencies and a zero dc field for 1; right: temperature
dependence of the in-phase ' and out-of-phase '' at different frequencies
and a 1000 Oe dc field for 1.
Fig. 3 Temperature dependence of magnetic susceptibilities in the form of
-1
χMT vs. T and χM vs. T for 1 at 1 kOe. The solid line of the χM-1 vs. T
illustration corresponds to the best fit from 300 K to 2 K.
To investigate the influence of the metal ion on the magnetic
properties, magnetic measurements on 2 were performed. The
magnetic behaviors of 2 are different to those of 1 (Fig. 6). At 300
K, the MT value is 73.73 emu mol-1 K for compound 2, larger than
the expected value for four magnetically noninteracting CoII ions (S
= 3/2, g = 2) and four magnetically isolated DyIII ions (J = 15/2, g =
4/3). As reported in many other Co-containing compounds, the
4 | J. Name., 2012, 00, 1-3
This journal is © The Royal Society of Chemistry 2012

View Article Online
DOI: 10.1039/C6DT00951D
Page 5 of 7
Journal Name
Dalton Transactions
ARTICLE
room temperature MT value is usually higher than the expected
spin-only one because of the orbital contribution of the high-spin
CoII ions.14 Upon cooling from 300 to 2 K, the MT values decrease
gradually and then more rapidly below 170 K to the minimum
value of 57.37 emu mol-1 K at 10 K, which may be resulted from
Stark level splitting in the lanthanide ions in the weak crystal-field.
After that MT value appears a slight increase until 2 K and reaches
59.76 emu mol-1 K, indicating that very weak ferromagnetic
coupling within the spin centers occurs.20
centers. The synthetic strategy used in this work will be further
extended for obtaining more molecule-based magnetic materials
with desired properties.
Acknowledgements
The authors appreciate the financial support from Natural
Science Foundation of China (21272167), and A Project
Funded by the Priority Academic Program Development of
Jiangsu Higher Education Institution.
Notes and references
a
College of Chemistry, Chemical Engineering and Materials Science,
Soochow
University,
Suzhou
215123,
China.
E-mail:
liyahong@suda.edu.cn
b
Qinghai Institute of Salt Lakes, Chinese Academy of Sciences, Xining
810008, China.
CCDC 1030935 and 1030933 for complexes
1 and 2, respectively.
References
1
(a) R. E. P. Winpenny, in Comprehensive Coordination
Fig. 6 Temperature dependence of magnetic susceptibilities in the form of
Chemistry II, ed. J. A. McCleverty and T. J. Meyer, Elsevier,
Amsterdam, 2004, vol. 7, 125-175; (b) O. Kahn, Magnetism:
A Supramolecular Function (NATO Science Series), 1995; (c)
J. W. Steed and J. L. Atwood, Supramolecular Chemistry
(Wiley), 2000; (d) D. Gatteschi, R. Sessoli and J. Villain,
Molecular Nanomagnets, Oxford University Press, Oxford,
2006.
-1
-1
χMT vs. T and χM vs. T for 2 at 1 kOe. The solid line of the χM vs. T
illustration corresponds to the best fit from 300 K to 50 K
Dynamic studies of complex 2 have been explored under the
same measurement conditions for complex 1. As shown in Fig. S7,
all of the signals of ' and '' are very weak but frequency-
dependent without any peaks occurring. Furthermore, the ac
susceptibility was measured under 2000 Oe dc field at 999 Hz, no
peaks neither in phase nor out of phase were found (Fig. S8). There
are two factors may responsible for this phenomenon, namely,
quantum tunneling and anti-ferromagnetic interactions.
2
(a) M. N. Leuenberger and D. Loss, Nature, 2001, 410, 789-
793; (b) D. L. Long, E. Burkholder and L. Cronin, Chem. Soc.
Rev., 2007, 36, 105-121; (c) A. R. Rocha, V. M. García-
Suárez, S. W. Bailey, C. J. Lambert, J. Ferrerand and S.
Sanvito, Nat. Mater., 2005, 4, 335-339; (d) A. J. Tasiopoulos,
A. Vinslava, W. Wernsdorfer, K. A. Abboud and G. Christou,
Angew. Chem., Int. Ed., 2004, 43, 2117-2121; (e) R. Vincent,
S. Klyatskaya, M. Ruben, W. Wernsdorfer and F. Balestro,
Nature, 2012, 488, 357-360; (f) D. M. Low, L. F. Jones, A.
Bell, E. K. Brechin, T. Mallah, E. Riviere, S. J. Teat and E. J.
L. McInnes, Angew. Chem., Int. Ed., 2003, 42, 3781-3784; (g)
M. Ganzhorn, S. Klyatskaya, M. Ruben and W. Wernsdorfer,
Nat. Nanotechnol., 2013, 8, 165-169; (h) A. Candini, S.
Klyatskaya, M. Ruben, W. Wernsdorfer and M. Affronte,
Nano Lett., 2011, 11, 2634-2639; (i) R. Vincent, S.
Klyatskaya, M. Ruben, W. Wernsdorfer and F. Balestro,
Nature, 2012, 488, 357-360; (j) S. T. Liddle and J. van
Slageren, Chem. Soc. Rev., 2015, 44, 6655-6669; (k) Y. Z.
Zheng, Z. P. Zheng and X. M. Chen, Coord. Chem. Rev.,
2014, 258-259, 1-15; (l) H. L. Sun, Z. M. Wang and S. Gao,
Coord. Chem. Rev., 2010, 254, 1081-1100.
As reported before, the magnetic property of CoII system is
usually in marked contrast with the NiII system with a similar
structure.21 It is usually considered that ferromagnetic interactions
were in favor of SMMs behavior due to larger ground state. The
differences in the strength of ferromagnetic interactions between
magnetic centers in 1 and 2 may finally result in different magnetic
properties of the two complexes.
Conclusions
In summary, two new 3d-4f heterotetrametallic 1D double-chain
frameworks built from [Dy2M2]n (M = Ni(1), Co(2)) unit have been
successfully
obtained
using
2-{[(2-hydroxy-3-
3
4
(a) M. Soler, W. Wernsdorfer, K. Folting, M. Ping and G.
Christou, J. Am. Chem. Soc., 2004, 126, 2156-2165; (b) A. J.
Tasiopoulos, A. Vinslava, W. Wernsdorfer, K. A. Abboud
and G. Christou, Angew. Chem., Int. Ed., 2004, 43, 2117-
2121.
methoxyphenyl)methylidene]amino}benzoic acid (H2L) as the
ligand under solvothermal conditions. They both exhibit ladder-like
double-chain structures with two single-helical chains running
along c-axis and possessing opposite chirality. Different magnetic
dynamic behaviors were observed in 1 and 2, which is may be
associated with distinct magnetic interactions of different metal
J. F. Wu, L. Zhao, P. Zhang, L. Zhang, M. Guo and J. K.
Tang, Dalton Trans., 2015, 44, 11935-11942.
This journal is © The Royal Society of Chemistry 2012
J. Name., 2012, 00, 1-3 | 5

View Article Online
Dalton Transactions
DOI: 10.1039/C6DT00P95a1gDe 6 of 7
ARTICLE
Journal Name
5
6
N. Ishikawa, M. Sugita, T. Ishikawa, S.-Y. Koshihara and Y.
Kaizu, J. Am. Chem. Soc., 2003, 125, 8694-8695.
7981-7993; (c) J. W. Zhao, Y. Z. Li, F. Ji, J. Yuan, L. J.
Chen and G. Y. Yang, Dalton Trans., 2014, 43, 5694-5706.
(a) L. Sorace, C. Benelli and D. Gatteschi, Chem. Soc. Rev.,
2011, 40, 3092-3104; (b) Y. N. Guo, G. F. Xu, W.
Wernsdorfer, L. Ungur, Y. Guo, J. K. Tang, H. J. Zhang, L. F.
Chibotaru and A. K. Powell, J. Am. Chem. Soc., 2011, 133,
11948-11951; (c) H. Q. Tian, M. Wang, L. Zhao, Y. N. Guo,
Y. Guo, J. K. Tang and Z. L. Liu, Chem. Eur. J., 2012, 18,
442-445.
19
G. F. Xu, Q. L. Wang, P. Gamez, Y. Ma, R. Clerac, J. Tang,
S. P. Yan, P. Cheng and D. Z. Liao, Chem. Commun., 2010,
46, 1506-1508.
20
21
S. J. Liu, J. P. Zhao, W. C. Song, S. D. Han, Z. Y. Liu and X.
H. Bu, Inorg. Chem., 2013, 52, 2103-2109.
X. M. Zhang, K. Wang, Y. Q. Wang and E. Q. Gao, Dalton
Trans., 2011, 40, 12742-12749.
7
8
V. Chandrasekhar, S. Hossain, S. Das, S. Biswas and J. P.
Sutter, Inorg. Chem., 2013, 52, 6346-6353.
F. Tuna, C. A. Smith, M. Bodensteiner, L. Ungur, L. F.
Chibotaru, E. J. L. McInnes, R. E. P. Winpenny, D. Collison
and R. A. Layfield, Angew. Chem., Int. Ed., 2012, 51, 6976-
6980.
9
K. Liu, W. Shi and P. Cheng, Coord. Chem. Rev., 2015, 289-
290, 74-122.
10
(a) F. Pointillart, K. Bernot, R. Sessoli and D. Gatteschi,
Chem. Eur. J., 2007, 13, 1602-1609; (b) C. Benelli and D.
Gatteschi, Chem. Rev., 2002, 102, 2369-2387; (c) L. Sorace,
C. Benelli and D. Gatteschi, Chem. Soc. Rev., 2011, 40,
3092-3104.
11
(a) S. D. Jiang, B. W. Wang, G. Su, Z. M. Wang and S. Gao,
Angew. Chem., Int. Ed., 2010, 49, 7448-7451; (b) M. Jeletic,
H. P. Lin, J. J. Le Roy, I. Korobkov, S. I. Gorelsky and M.
Murugesu, J. Am. Chem. Soc., 2011, 133, 19286-19289; (c) F.
Tuna, C. A. Smith, M. Bodensteiner, L. Ungur, L. F.
Chibotaru, E. J. L. Mcinnes, R. E. P. Winpenny, D. Collison
and R. A. Layfield, Angew. Chem., Int. Ed., 2012, 51, 6976-
6980; (d) Y. N. Guo, G. F. Xu, W. Wernsdorfer, L. Ungur, Y.
Guo, J. K. Tang, H. J. Zhang, L. F. Chibotaru and A. K.
Powell, J. Am. Chem. Soc., 2011, 133, 11948-11951.
12
C. J. Milios, A. Vinslava, W. Wernsdorfer, A. Prescimone, P.
A. Wood, S. Parsons, S. P. Perlepes, G. Christou and E. K.
Brechin, J. Am. Chem. Soc., 2007, 129, 6547-6561.
13
14
S. C. Xiang, S. M. Hu, T. L. Sheng, J. S. Chen and X. T. Wu,
Chem. Eur. J., 2009, 15, 12496-12502.
G. Abbas, Y. H. Lan, V. Mereacre, W. Wernsdorfer, R.
Clérac, G. Buth, M. T. Sougrati, F. Grandjean, G. J. Long, C.
E. Anson and A. K. Powell, Inorg. Chem., 2009, 48, 9345-
9355.
15
16
(a) S. X She, M. J. Zaworotko, W. Liu, Z. X. Zhang and Y. H.
Li, CrystEngComm, 2013, 15, 5003-5006; (b) S. X. She, Y.
M. Chen, M. J. Zaworotko, W. Liu, Y. Y. Cao, J. Wu and Y.
H. Li, Dalton Trans., 2013, 42, 10433-10438.
(a) F. Pointillart, K. Bernot, R. Sessoli and D. Gatteschi,
Chem. Eur. J., 2007, 13, 1602-1609; (b) T. Yamaguchi, Y.
Sunatsuki, H. Ishida, M. Kojima, H. Akashi, N. Re, N.
Matsumoto, A. Pochaba and J. Mrozinski, Inorg. Chem.,
2008, 47, 5736-5745; (c) T. Shiga, N. Ito, A. Hidaka, H.
Ohkawa, S. Kitagawa and M. Ohba, Inorg. Chem., 2007, 46,
3492-3501; (d) J. P. Sutter, S. Dhers, R. Rajamani, S.
Ramasesha, J. P. Costes, C. Duhayon and L. Vendier, Inorg.
Chem., 2009, 48, 5820-5828; (e) J. -P. Costes, T. Yamaguchi,
M. Kojima and L. Vendier, Inorg. Chem., 2009, 48, 5555-
5561.
17
18
G. M. Sheldrick, Acta Cryst., 2008, A64, 112-122.
(a) K. C. Mondal, B. Gole, Y. Song, S. R. Batten, D. R.
Turner, and P. S. J. Mukherjee, Chem. Sci., 2011, 123, 807-
818; (b) J. W. Zhao, J. Luo, L. J. Chen, J. Yuan, H. Y. Li, P.
T. Ma, J. P. Wang and J. Y. Niu, CrystEngComm, 2012, 14,
6 | J. Name., 2012, 00, 1-3
This journal is © The Royal Society of Chemistry 2012

Page 7 of 7
Dalton Transactions
View Article Online
DOI: 10.1039/C6DT00951D
Two 3d-4f double helical chains including [Dy2M2]n (M = NiII
and CoII) cores exhibiting slow magnetic relaxation
Shixiong She, Yahong Li* and Wu Li
Two new heterometallic complexes with one-dimensional ladder-like double-helical chain structures were prepared.
They both exhibit interesting magnetic properties.