Design and construction of coordination polymers based on 2,2′-dinitro-4,4′-biphenyldicarboxylate and semi-rigid N-donor ligands: Diverse structures and magnetic properties

Article abstract of DOI:10.1039/c1dt11654a

Eight 2D and 3D coordination polymers, [Mn(NBPDC)(1,4-bimb)]_n (1), [Zn(NBPDC)(1,4-bimb)]_n (2), [Cd(NBPDC)(1,4-bimb)]_n (3), [Mn₂(NBPDC)₂(1,3-bimb)(H₂O)]_n (4), {Zn(NBPDC)(1,3-bimb)}_n (5), [Cd₂(NBPDC) ₂(1,3-bimb)₂(H₂O)]_n (6), [Mn(NBPDC)(4,4′-bimbp)]_n (7), and [Cd₂(NBPDC) ₂(4,4′-bimbp)₂]_n (8), (NBPDC = 2,2′-dinitro-4,4′-biphenyldicarboxyl acid, 1,4-bimb = 1,4-bis(imidazol-1-ylmethyl) benzene, 1,3-bimb = 1,3-bis(imidazol-1-ylmethyl) benzene, and 4,4′-bimbp = 4,4′-(bis(imidazol-l-ylmethylene)) biphenyl), have been prepared and structurally characterized. In these coordination polymers, NBPDC and three N-donor ligands link different metal ions and SBUs to construct diverse architectures. Compounds 1 and 3 are isomorphic, showing a two-fold interpenetrating pcu topology. Compound 2 presents a 2D (4, 4) net. Compound 4 is a hex framework built by the linkage of ligands with infinite rod-shaped SBUs. Compound 5 presents a unprecedented eight-fold interpenetrating sra topology. Compound 6 exhibits a unique 2D {6 ³}{6⁵.8} topology with four-fold interpenetrating structure. Compound 7 presents a 3D hex topology, and compound 8 shows a (4, 4) net. The magnetic properties of compounds 1, 4, and 7 have been characterized. Compound 1 displays interesting spin-canting antiferromagnetism and metamagnetism simultaneously. Compound 7 exhibits spin-canting antiferromagnetism. The Royal Society of Chemistry 2012.

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PAPER
Design and construction of coordination polymers based on 2,2′-dinitro-4,4′-
biphenyldicarboxylate and semi-rigid N-donor ligands: diverse structures and
magnetic properties†
Baiyan Li, Fen Yang, Yiming Zhang, Guanghua Li, Qi Zhou, Jia Hua, Zhan Shi* and Shouhua Feng
Received 2nd September 2011, Accepted 18th October 2011
DOI: 10.1039/c1dt11654a
Eight 2D and 3D coordination polymers, [Mn(NBPDC)(1,4-bimb)]n (1), [Zn(NBPDC)(1,4-bimb)]n (2),
[Cd(NBPDC)(1,4-bimb)]n (3), [Mn2(NBPDC)2(1,3-bimb)(H2O)]n (4), {Zn(NBPDC)(1,3-bimb)}n (5),
[Cd2(NBPDC)2(1,3-bimb)2(H2O)]n (6), [Mn(NBPDC)(4,4′-bimbp)]n (7), and [Cd2(NBPDC)2(4,4′-
bimbp)2]n (8), (NBPDC = 2,2′-dinitro-4,4′-biphenyldicarboxyl acid, 1,4-bimb = 1,4-bis(imidazol-1-
ylmethyl) benzene, 1,3-bimb = 1,3-bis(imidazol-1-ylmethyl) benzene, and 4,4′-bimbp = 4,4′-
(bis(imidazol-l-ylmethylene)) biphenyl), have been prepared and structurally characterized. In these
coordination polymers, NBPDC and three N-donor ligands link different metal ions and SBUs to
construct diverse architectures. Compounds 1 and 3 are isomorphic, showing a two-fold interpenetrating
pcu topology. Compound 2 presents a 2D (4, 4) net. Compound 4 is a hex framework built by the linkage
of ligands with infinite rod-shaped SBUs. Compound 5 presents a unprecedented eight-fold
interpenetrating sra topology. Compound 6 exhibits a unique 2D {63}{65.8} topology with four-fold
interpenetrating structure. Compound 7 presents a 3D hex topology, and compound 8 shows a (4, 4) net.
The magnetic properties of compounds 1, 4, and 7 have been characterized. Compound 1 displays
interesting spin-canting antiferromagnetism and metamagnetism simultaneously. Compound 7 exhibits
spin-canting antiferromagnetism.
Recently, coordination polymers based on two ligands such as
polycarboxylate and N-donor ligands have attracted lasting
Introduction
The design and construction of coordination polymers have
attracted increasing attention in the field of crystal engineering
due to their novel and diverse topologies and potential appli-
cations in many areas such as catalysis, gas adsorption and sep-
aration, optics, and magnetism.1–5 An important task of crystal
engineering is to synthesize coordination polymers with targeted
structure and expected properties. However, the investigation
into factors influencing the structural construction of functional
compounds has been a challenge because too many factors can
influence the structures of coordination polymers. These factors
mainly include organic ligands, metal ions, pH value of solution
and solvent effect, the ratio of metal-to-ligand and so on.6–9
Among these factors, the organic ligand is one of the most
important factors because its length, flexibility, steric effects and
angle of coordination atoms will lead in diverse structures of
coordination polymers.10
research interest because of the possibility to easily obtain a con-
trolled architecture by changing one of the two ligands.11 In pre-
vious work, we have used the rigid NBPDC (NBPDC = 2,2′-
dinitro-4,4′-biphenyldicarboxyl acid) and the flexible ligands
bpp (bpp = 1,3-bi(4-pyridyl)propane), bib (bib = 1,4-bis
(imidazol)butane), and bip (bip = 1,5-bis(imidazol)pentane) to
construct a series of coordination polymers.12 In order to investi-
gate the effect of length, flexibility, and angle of N-donor ligand
on the structures of the coordination polymers, we chose three
semi-rigid N-donor ligands 1,4-bis(imidazol-1-ylmethyl)
benzene (1,4-bimb),13 1,3-bis(imidazol-1-ylmethyl) benzene
(1,3-bimb),13b,13h,14
and
4,4′-(bis(imidazol-l-ylmethylene))
biphenyl (4,4′-bimbp)13l,15 with different features as one of the
mix ligands to construct coordination polymers (Scheme 1).
In this paper, eight coordination polymers exhibiting 2D or
3D structures were synthesized by reacting NBPDC and three
State Key Laboratory of Inorganic Synthesis and Preparative Chemistry,
College of Chemistry, Jilin University, Changchun, 130012, People’s
Republic of China. E-mail: zshi@mail.jlu.edu.cn
†Electronic supplementary information (ESI) available. CCDC reference
numbers 842364–842371 for complexes 1–8. For ESI and crystallo-
graphic data in CIF or other electronic format see DOI: 10.1039/
c1dt11654a
Scheme 1 Comparison of the three N-donor ligands.
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Scheme 2 Schematic representation of the diverse coordination modes
of NBPDC.
different N-donor ligands with different metal ions including
Mn2+, Zn2+, and Cd2+. The magnetic properties of compounds 1,
4, 7 have also been investigated.
Results and discussion
Description of crystal structures
Structure of [Mn(NBPDC)(1,4-bimb)]n (1). The asymmetry
unit of crystal 1 consists of one Mn(II) atom, one NBPDC mol-
ecule, and one 1,4- bimb molecule. The Mn(II) atom lies in a dis-
torted octahedral coordination sphere occupied by four oxygen
atoms from three different NBPDC molecules (Mn–O =
2.142–2.320 Å), and two nitrogen atoms of two 1,4-bimb mol-
ecules (Mn–N = 2.243–2.307 Å) (Fig. S1†). Two adjacent
Mn(II) atoms are linked by a carboxyl group to form a Mn2 unit.
Each Mn2 unit links four Mn2 units around it through four
NBPDC with mode A (Scheme 2) to construct a 2D layer along
the bc plane (Fig. 1a). Two adjacent layers are interconnected
through 1,4-bimb molecules along the a axis direction to build a
3D net (Fig. 1b). It is interesting that two identical 3D nets are
interweaved together to form a two-fold interpenetrating network
structure (Fig. 1c). From the view of topology, if Mn2 clusters
are viewed as nodes and the ligands as spacers, then crystal 1
will exhibit a pcu topology (Fig. S2†).
Fig. 1 (a) 2D layer of crystal 1 (nitro groups of NBPDC and hydrogen
atoms have been omitted for clarity), (b) 3D framework of crystal 1
(green: 1,4-bimb molecules; nitro groups of NBPDC and hydrogen
atoms have been omitted for clarity), (c) two-fold interpenetrating
network of crystal 1 (nitro groups of NBPDC and hydrogen atoms have
been omitted for clarity).
Structure of [Zn(NBPDC)(1,4-bimb)]n (2). The asymmetry
unit of crystal 2 includes one Zn(II) atom, one NBPDC molecule,
and one 1,4-bimb molecule. The Zn(II) atom is in tetrahedral
configuration coordinated by two oxygen atoms from two differ-
ent NBPDC molecules (Zn–O = 1.965–2.001 Å) and two nitro-
gen atoms of two 1,4-bimb (Zn–N = 1.993–2.038 Å) (Fig. S3†).
NBPDC links two adjacent Zn(II) atoms with mode
B
(Scheme 2) along the c axis direction to construct a 1D zigzag
chain (Fig. 2a). Two 1D chains are interconnected through 1,4-
bimb molecules to form a 2D wave-shaped layer with (4, 4) net
(Fig. 2b, S4†). These layers construct the structure of compound
1 by weak interactions (Fig. S5†). The distance between the
hydrogen atoms of methylene in 1,4-bimb and the carboxyl
oxygen atoms of NBPDC is 2.68 Å.
Fig. 2 (a) 1D chain of crystal 2 (nitro groups of NBPDC and hydrogen
atoms have been omitted for clarity), (b) 2D layer of crystal 2 (green:
1,4-bimb molecules; nitro groups of NBPDC and hydrogen atoms have
been omitted for clarity).
Structure of [Cd(NBPDC)(1,4-bimb)]n (3). Crystal 3 has the
same structure as 1 except different metal atoms, so the structure
of crystal 3 will not be depicted here.
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Fig. 3 (a) 1D rod-shaped SBU of crystal 4, (b) 3D subnet of crystal 4
(nitro groups of NBPDC, hydrogen atoms, and free water molecules
have been omitted for clarity), (c) 3D structure of crystal 4 (green and
purple: 1,3-bimb molecules; nitro groups of NBPDC, hydrogen atoms,
and free water molecules have been omitted for clarity).
Structure of [Mn2(NBPDC)2(1,3-bimb)(H2O)]n (4). There are
one Mn(II) atom, one NBPDC molecule, half of a 1,3-bimb mol-
ecule, and half of a free water molecule in the asymmetry unit of
crystal 4. The Mn(II) is in a trigonal bipyramid geometry consist-
ing of four oxygen atoms of NBPDC (Mn–O = 2.082–2.153 Å)
and one nitrogen atom of the 1,3-bimb molecule (Mn–N =
2.190 Å) (Fig. S6†). Adjacent Mn(II) atoms are interconnected
through carboxyl group oxygen atoms to form a 1D rod-shaped
SBU (Fig. 3a). Each rod-shaped SBU links four adjacent rod-
shaped SBUs constructing a 3D subnet (Fig. 3b). NBPDC mol-
ecules exhibit mode C in crystal 4 (Scheme 2). 1,3-bimb mol-
ecules link two rod-shaped chains along the a axis direction to
construct an extended 3D framework with hex topology (Fig. 3c,
S7†).
Fig. 4 (a) 1D chain of crystal 5 (nitro groups of NBPDC and hydrogen
atoms have been omitted for clarity), (b) 3D framework of crystal 5
(purple: 1,3-bimb molecules; nitro groups of NBPDC, hydrogen atoms,
and some disordered atoms have been omitted for clarity), (c) sra
topology of crystal 5, (d) eight-fold interpenetrating sra topology of
crystal 5.
Structure of {Zn(NBPDC)(1,3-bimb)}n (5). Single crystal X-
ray analysis revealed that the asymmetric unit of 5 consists of
one Zn(II) atom, one NBPDC molecule, and two half 1,3-bimb
molecules. The Zn(II) atom is in a tetrahedral coordination
5 is that eight identical 3D frameworks are interweaved together
to form an eight-fold interpenetrating structure (Fig. 4d). To the
best of our knowledge, a compound with eight-fold interpene-
trating sra topology is unprecedented.
sphere coordinated by two oxygen atoms (Zn–O
=
1.966–1.968 Å) from two distinct NBPDC molecules and two
nitrogen atoms (Zn–N = 2.004–2.006 Å) of two 1,3-bimb mol-
ecules (Fig. S8†). NBPDC molecules with mode B (Scheme 2)
link two adjacent Zn(II) atoms to form a 1D zigzag chain along
the c axis direction (Fig. 4a). Each 1D chain links three identical
1D chains through 1,3-bimb molecules to form a 3D framework
with sra topology (Fig. 4b, 4c). An interesting feature of crystal
Structure of [Cd2(NBPDC)2(1,3-bimb)2(H2O)]n (6). The
asymmetry unit of crystal 6 consists of two Cd(II) atoms, two
NBPDC molecules, two 1,3-bimb molecules and one free water
molecule. As shown in Fig. S9,† the two Cd(II) atoms are both
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Fig. 6 (a) 1D rod-shaped SBU of crystal 7, (b) 2D layer of crystal 7
(nitro groups of NBPDC and hydrogen atoms have been omitted for
clarity), (c) 3D framework of crystal 7 (purple: 4,4′-bimbp molecules;
nitro groups of NBPDC and hydrogen atoms have been omitted for
clarity).
Fig. 5 (a) 1D chain of crystal 6 (nitro groups of NBPDC and hydrogen
atoms have been omitted for clarity), (b) 2D layer of crystal 6 (green:
1,3-bimb molecules; nitro groups of NBPDC, hydrogen atoms, and free
water molecules have been omitted for clarity), (c) four-fold interpene-
trating network of crystal 6 (nitro groups of NBPDC, hydrogen atoms,
and free water molecules have been omitted for clarity).
molecules exhibit mode C in crystal 7. 4,4′-bimbp molecules
link two adjacent layers constructing a 3D framework (Fig. 6c).
From the view of topology, each rod-shaped SBU links six rod-
shaped SBUs around it through NBPDC and 4,4′-bimbp mol-
ecules to form a hex topology (Fig. S12†).
in distorted octahedral coordination spheres coordinated by four
oxygen atoms of NBPDC (Cd–O = 2.284–2.501 Å) and two
nitrogen atoms of 1,3-bimb molecules (Cd–N = 2.222–2.266 Å),
respectively. Two adjacent Cd(II) atoms are interconnected by
NBPDC molecules with mode D (Scheme 2) to construct a 1D
zigzag chain along the b direction (Fig. 5a). The 1D chains are
bridged by 1,3-bimb molecules to form a 2D layer (Fig. 5b). If
Cd(II) atoms are viewed as nodes, the crystal will exhibit a rare
(3, 4)-connected net with point (Schlafli) symbol for net: {63}
{65.8}. It is interesting to note that each 2D layer interweaves
with three adjacent layers to form a four-fold interpenetrating net
(Fig. 5c, S10†). Free water molecules fill in the framework
through H-bond interactions.
Structure of [Cd2(NBPDC)2(4,4′-bimbp)2]n (8). Crystal 8 pos-
sesses an asymmetry unit consisting of two Cd(II) atoms, two
NBPDC molecules, and two 4,4′-bimbp molecules. The two
Cd(II) atoms are both in distorted octahedral coordination
environments coordinated by four oxygen atoms of NBPDC
molecules (Cd–O = 2.328–2.423 Å) and two nitrogen atoms of
4,4′-bimbp molecules (Cd–N = 2.216–2.236 Å), respectively
(Fig. S13†). NBPDC molecules with mode D bridge Cd(II)
atoms to form a 1D chain along the c axis direction, which is
further linked through 4,4′-bimbp molecules to construct a 2D
layer along the ac plane with (4, 4) topology (Fig. 7, S14†). Two
adjacent layers are linked through weak interactions to build a
3D supermolecular net. The distance between the hydrogen
atoms of methylene in 4,4′-bimbp and the carboxyl oxygen
atoms of NBPDC is 2.73 or 2.80 Å.
Structure of [Mn(NBPDC)(4,4′-bimbp)]n (7). The asymmetry
unit of crystal 7 includes two half Mn(II) atoms, one NBPDC
molecule, and one 4,4′-bimbp molecule. Two Mn(II) atoms are
both in octahedral configurations in which the six coordination
sites of the Mn(II) atom are occupied by four oxygen atoms of
four different NBPDC molecules (Mn–O = 2.191–2.220 Å) and
two nitrogen atoms of 4,4′-bimbp molecules (Mn–N
=
Effects of ligands and metal ions on the structure of com-
pounds. As discussed above, NBPDC presents four different
coordination modes, which link different metal ions to form
various inorganic building blocks. NBPDC with mode A or C is
inclined to construct clusters or infinite SBUs, whereas NBPDC
with mode B or D tends to yield single metal atom building
2.223–2.240 Å), respectively (Fig. S11†). Adjacent Mn(II) atoms
are bridged by carboxyl group oxygen atoms to form a 1D rod-
shaped SBU along the a direction (Fig. 6a). Two 1D chains are
interconnected by biphenyl parts of NBPDC to form a 2D layer
along the ab plane (Fig. 6b). Similar to crystal 4, NBPDC
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Fig. 7 2D layer of crystal 8 (blue: 4,4′-bimbp molecules; nitro groups
of NBPDC and hydrogen atoms have been omitted for clarity).
−1
Fig. 8 Temperature dependence of χmT and χm of 1 at H = 1 kOe
from 2 to 300 K.
blocks. For example, the building blocks are clusters in crystals
1 and 3, and infinite rod-shaped SBUs in crystals 4 and 7; for
the other compounds, the building blocks are single metal ions.
The difference in building blocks is an important factor affecting
the structural diversity of coordination polymers due to different
coordination directions and coordination numbers. Another
important factor is the three N-donor ligands (1,4-bimb, 1,3-
bimb, 4,4′-bimbp) with different bridging length and angle of
the coordination atoms. This conclusion can be drawn by com-
paring the structures of crystal 2 and crystal 5. In the structures
of crystals 2 and 5, NBPDC molecules with the same coordi-
nation modes bridge Zn(II) ions with the same configurations to
construct similar 1D chains. However, they give different struc-
tures including (4, 4) and sra topologies due to different linking
directions of two N-donor ligands. A similar conclusion can be
achieved by comparing crystal 6 and crystal 8. The diverse struc-
tures afforded by different N-donor ligands may be attributed to
spatial effect, linking length, angle of coordination atoms, match-
ing of NBPDC and N-donor, etc. In addition, the metal centres
also play an important role in constructing coordination poly-
mers. The frameworks of the final compounds are related to
coordination configurations of metal ions, metal radii, coordi-
nation environments, etc. A clear example is compounds 5 and
6. They have the same ligands but different structures because of
different metal ions.
Fig. 9 ZFC and FC curves at H = 100 Oe from 2 to 80 K of 1.
As shown in Fig. 9, the field-cooled (FC) and zero-field-
cooled (ZFC) susceptibities (100 Oe) diverge at about 50 K,
indicating the irreversible transition of the weak ferromagnetism.
Furthermore, the susceptibility in low temperature range is field
dependent, as shown in Fig. S15,† which is consistent with spin
canting. Further experimental evidence for the spin-canted weak
ferromagnetism and magnetic phase transition in 1 comes from
field-dependent isothermal magnetization measurements
(Fig. 10). The magnetization value at 2 K and 5 T amounts to
Magnetic properties. Variable temperature d.c. magnetic sus-
ceptibility data were measured at 1000 Oe in the temperature
range 2–300 K. For 1, the χMT value of approximately 4.61 cm3
K mol−1 at room temperature is close to the expected spin-only
value for an isolated Mn2+ ion (4.38 cm3 K mol−1, g = 2.0)
(Fig. 8). The value of χMT remains almost constant as the temp-
erature is decreased until 120 K, then decreases very slowly to a
minimum of 4.40 cm3 K mol−1 at 54 K, then increases up to
6.7 cm3 K mol−1 at 38 K and finally drops sharply upon further
cooling. The Curie–Weiss fits above 54 K give Weiss constants
of −2.17 K, demonstrating the presence of a very weak antiferro-
magnetic interaction between spin centres. The magnetic data
above 54 K were fitted to the Hamilton equation Ĥ = −JŜ1Ŝ2
with the best parameters g = 2.08 and J = −0.98 cm−1. The
negative value of J confirms the weak antiferromagnetic inter-
action again. The magnetic behavior below 54 K may be due to
spin canting as described below.
Fig. 10 Plots of the magnetization (M) vs. H of 1 at 2 K. The inset
shows the derivative of M at 2 K against H.
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−1
Fig. 12 Temperature dependence of χmT and χm of 7 at H = 1 kOe
from 2 to 300 K.
−1
Fig. 11 Temperature dependence of χmT and χm of 4 at H = 1 kOe
from 2 to 300 K.
4.5 Nβ, which is smaller than the theoretical saturation value
(Ms = 5 Nβ). A hysteresis loop (Fig. S16†) is observed with a
coercive field of 150 Oe and a remnant magnetization of 0.014
Nβ. The respective canting angle, calculated from tan−1(Mr/Ms),
where Mr is the remnant magnetization, which is about 0.16°.
Notably, the field-dependent magnetization at 2 K for compound
1 has an S-shaped curve, suggesting a metamagnetic behavior.
The dM/dH versus H curve displays a relative maximum, imply-
ing the field-induced metamagnetic transition and the critical
field is 20.1 kOe.
For 4, the χMT value of approximately 4.00 cm3 K mol−1 at
room temperature is smaller than the spin-only one expected for
a bivalent uncorrelated manganese ion (4.38 cm3 K mol−1, g =
2.0) (Fig. 11). The deviation from the expected value of χMT at
room temperature may be due to intramolecular antiferromag-
netic interactions. A gradual decrease is observed from room
temperature to 100 K, and below this temperature the χMT value
falls very sharply. The best fit with the Curie–Weiss law gives C
= 4.20 cm3 mol−1 K and θ = −12.87 K. The negative value of θ
indicates the interaction between the spin centres is antiferromag-
netic. The magnetic data over the whole temperature range could
be well fitted by a Fisher 1D Heisenberg chain model (S = 5/2,
Ĥ = −2JŜiŜj resulting in J = −2.32 cm−1, g = 2.03 and R = 1.32
× 10−6 (R is defined as [(χM)obs−(χM)calcd]2/[(χM)obs]2). We
also present the isothermal magnetization curve (2 K) here
(Fig. S17†). The magnetization value increases almost linearly
with the applied magnetic field and reaches a value of 0.86 Nβ at
50 kOe, far from the saturation (5 Nβ) for an spin-only Mn2+
ion, confirming the antiferromagnetic interaction again.
Fig. 13 ZFC and FC curves at H = 100 Oe from 2 to80 K of 7.
The low-temperature ferromagnetic-like behavior of 7 may be
due to spin canting. The field-cooled (FC) and zero-field-cooled
(ZFC) susceptibities are measured at 100 Oe in the range
2–80 K (Fig. 13). The divergence indicates the existence of
weak ferromagnetism. Furthermore, the field dependence of the
magnetization, M(H) at 2 K (Fig. S18†), shows a steady increase
to 1.52 Nβ at 50 kOe, much less than the expected saturation
value of 5 Nβ for one Mn2+ ion with S = 5/2 and g = 2, consist-
ent with its observed spin-canted behavior. The hysteresis loop
measured at 2 K is consistent with a weak ferromagnetism
(Fig. S19†). The remnant magnetization is 0.0074 Nβ, and the
coercive field is ca. 110 Oe. This confirms the behavior of weak
ferromagnetism due to spin canting again, and the canting angle
giving by the equation φ = tan−1(Mr/Ms) is about 0.086°, where
Mr is the remnant magnetization and Ms = gS is the expected sat-
uration magnetization if all of the spins are aligned
ferromagnetically.
For 7, at room temperature, the χMT value is about 4.00 cm3
K mol−1, which is somewhat below the expected value for an
isolated manganese ion and nearly keeps constant to 150 K.
Below this temperature the χMT decreases smoothly and reaches
a minimum value of 3.54 cm3 K mol−1 at 50 K, then increases
sharply to a maximum value of 4.62 cm3 K mol−1 at 40 K, and
finally drops rapidly upon further cooling (Fig. 12). The temp-
erature dependence of the reciprocal susceptibility (χ−1) above
54 K obeys the Curie–Weiss law with a Weiss constant of
−2.93 K, indicating a weak intrachain antiferromagnetic inter-
action between the Mn2+ ions. The magnetic data above 54 K
could be fitted by a Fisher 1D Heisenberg chain model (S = 5/2,
Ĥ = −2JŜiŜj) very well, resulting in J = −1.10 cm−1, g = 2.00
and R = 1.04 × 10−7 (R is defined above).
Conclusions
Eight new coordination polymers exhibiting diverse structures
have been synthesized by reacting NBPDC molecules and three
N-donor ligands (1,4-bimb, 1,3-bimb, 4,4′-bimbp) with different
metal ions. The diverse architectures and other interesting fea-
tures of these compounds have been identified, such as different
dimensional frameworks, molecular topology, interpenetration,
and weak interactions (hydrogen bonding, π–π stacking
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interactions, etc.). The structural diversity indicates that organic
ligands and metal ions can exert great influence on the structure
of the final assembly. The magnetic properties of compounds 1,
4, and 7 have been studied.
(KBr, cm−1): 3462(w), 3127(w), 3080(w), 1640(s), 1598(s),
1525(s), 1409(s), 1342(s), 1085(m), 781(s), 656(m).
Synthesis of {Zn(NBPDC)(1,3-bimb)}n (5). The same syn-
thetic procedure as for 4 was used except that Mn(AC)2 was
replaced by ZnSO4·7H2O, giving colorless block crystals. Yield:
32% (based on Zn). Elemental analysis (%): Calcd for 5: C
53.01, H 3.16, N 13.25. Found: C 53.32, H 3.02, N 13.21. IR
(KBr, cm−1): 3378(m), 3138(s), 1619(s), 1530(s), 1488(s), 1378
(s), 1242(s), 1117(s), 828(s), 786(s).
Experimental
Materials and physical measurements
All reagents and solvents were commercially available except for
NBPDC, (1,4-bimb), (1,3-bimb), and (4,4′-bimbp), which were
synthesized according to the literature.16 Elemental analyses
were performed on a Perkin-Elmer 2400 element analyzer. IR
spectra were recorded on a Nicolet Impact 410 FTIR spec-
trometer using KBr pellet. PXRD data were collected on a
Rigaku D/max 2550 X-ray Powder Diffractometer. Variable-
temperature magnetic susceptibility data were obtained with
SQUID magnetometer (Quantum Design, MPMS-5) in the temp-
erature range 2–300 K by using an applied field of 1000Oe.
Pascal’s constants were used to estimate the diamagnetic correc-
tions, which were subtracted from the experimental susceptibility
to give the molar paramagnetic susceptibility (χm). Fluorescent
emission spectra for the solid samples were recorded on a
Perkin-Elmer LS 55 luminescence spectrometer. TG analysis
was performed on a TGA Q500 V20.10 Build 36.
Synthesis of [Cd2(NBPDC)2(1,3-bimb)2(H2O)]n (6). The same
synthetic procedure as for 4 was used except that Mn(AC)2 was
replaced by Cd(AC)2·2H2O, giving colorless block crystals.
Yield: 22% (based on Cd). Elemental analysis (%): Calcd for 6:
C 48.70, H 3.04, N 12.18. Found: C 48.82, H 2.96, N 12.06. IR
(KBr, cm−1): 3541(m), 3132(m), 1588(s), 1525(s), 1478(m),
1405(s), 1347(s), 1237(m), 1090(s), 828(s), 729(s).
Synthesis of [Mn(NBPDC)(4,4′-bimbp)]n (7). The same syn-
thetic procedure as for 1 was used except that 1,4-bimb was
replaced by 4,4′-bimbp, giving colorless block crystals. Yield:
35% (based on Mn). Elemental analysis (%): Calcd for 7: C
58.32, H 3.43, N 12.01. Found: C 58.25, H 3.48, N 12.06. IR
(KBr, cm−1): 3436(w), 3143(w), 1645(s), 1614(s), 1530(s), 1399
(s), 1342(s), 1085(m), 938(w), 823(w), 791(m).
Synthesis of [Cd2(NBPDC)2(4,4′-bimbp)2]n (8). The same syn-
thetic procedure as for 7 was used except that Mn(AC)2 was
replaced by CdCl2, giving colorless block crystals. Yield: 41%
(based on Cd). Elemental analysis (%): Calcd for 8: C 53.90, H
3.17, N 11.10. Found: C 53.85, H 3.28, N 11.02. IR (KBr,
cm−1): 3436(w), 3138(w), 1703(w), 1588(s), 1530(s), 1399(s),
1347(s), 1237(m), 1090(m), 833(m), 781(m).
Synthesis of [Mn(NBPDC)(1,4-bimb)]n (1). A mixture of
NBPDC (0.054 g, 0.16 mmol), 1,4-bimb (0.072 g, 0.30 mmol),
Mn(AC)2 (0.061 g, 0.18 mmol), and H2O (5 mL) was heated in
a 20 mL Teflon-lined autoclave at 160 °C for 3 d, followed by
slow cooling (5 °C h−1) to room temperature. The resulting
mixture was washed with water, and colorless block crystals
were collected and dried in air. Yield: 28% (based on Mn).
Elemental analysis (%): Calcd for 1: C 53.89, H 3.20, N 13.47.
Found: C 54.01, H 3.15, N 13.42. IR (KBr, cm−1): 3609(m),
3467(m), 3117(m), 1624(s), 1530(s), 1405(s), 1347(s), 1085(s),
781(s).
X-Ray structure determinations. The data collection and
structural analysis of crystals 1–3, 7, and 8 were performed on a
Rigaku RAXIS-RAPID equipped with a narrow-focus, 5.4 kW
sealed tube X-ray source (graphite-monochromated Mo-Kα radi-
ation, λ = 0.71073 Å). The data processing was accomplished
with the PROCESS-AUTO processing program. The data collec-
tion and structural analysis of crystals 4–6 were performed on a
Bruker SMART CCD diffractometer equipped with a graphite
monochromator. The SMART software was used for data collec-
tion, for indexing the reflections and for determining the unit
cell parameters; the collected data were integrated by using the
SAINT software. All data were collected at a temperature of 20
2 °C. Direct methods were used to solve the structure using the
SHELXL crystallographic software package. All non-hydrogen
atoms were easily found from the difference Fourier map. All
non-hydrogen atoms were refined anisotropically. Basic infor-
mation pertaining to crystal parameters and structure refinement
is summarized in Table S1.†
Synthesis of [Zn(NBPDC)(1,4-bimb)]n (2). The same synthetic
procedure as for 1 was used except that Mn(AC)2 was replaced
by ZnCl2, giving colorless block crystals. Yield: 35% (based on
Zn). Elemental analysis (%): Calcd for 2: C 53.01, H 3.16, N
13.25. Found: C 53.22, H 3.09, N 13.24. IR (KBr, cm−1): 3472
(m), 3132(m), 1697(m), 1619(s), 1525(s), 1384(s), 1336(s),
1242(s), 1096(s), 954(m), 761(m).
Synthesis of [Cd(NBPDC)(1,4-bimb)]n (3). The same synthetic
procedure as for 1 was used except that Mn(AC)2 was replaced
by Cd(NO3)2·4H2O, giving colorless block crystals. Yield: 39%
(based on Cd). Elemental analysis (%): Calcd for 3: C 49.35, H
2.94, N 12.34. Found: C 49.42, H 3.88, N 12.42. IR (KBr,
cm−1): 3483(m), 3106(s), 1975(w), 1609(s), 1530(s), 1394(s),
1352(s), 1090(s), 917(s), 786(s).
Acknowledgements
Synthesis of [Mn2(NBPDC)2(1,3-bimb)(H2O)]n (4). The same
synthetic procedure as for 1 was used except that 1,4-bimb was
replaced by 1,3-bimb, giving colorless block crystals. Yield:
28% (based on Mn). Elemental analysis (%): Calcd for 4: C
49.09, H 2.27, N 10.91. Found: C 49.21, H 2.18, N 10.83. IR
This work was supported by the Foundation of the National
Natural Science Foundation of China (no. 20971054 and
90922034), Specialized Research Fund for the Doctoral Program
of Higher Education, and China Postdoctoral Science
Foundation.
This journal is © The Royal Society of Chemistry 2012
Dalton Trans., 2012, 41, 2677–2684 | 2683

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8 (a) L. Pan, X. Huang, J. Li, Y. Wu and N. Zheng, Angew. Chem., Int.
Ed., 2000, 39, 527; (b) S. L. Li, K. Tan, Y. Q. Lan, J. S. Qin, M. N. Li,
D. Y. Du, H. Y. Zang and Z. M. Su, Cryst. Growth Des., 2010, 10, 1699;
(c) C.-P. Li and M. Du, Chem. Commun., 2011, 47, 5958.
9 (a) M. L. Tong, S. L. Zheng and X. M. Chen, Chem.–Eur. J., 2000, 6,
3729; (b) R. Q. Fang and X. M. Zhang, Inorg. Chem., 2006, 45, 4801;
(c) F. Y. Cui, K. L. Huang, Y. Q. Xu, Z. G. Han, X. Liu, Y. N. Chi and
C. W. Hu, CrystEngComm, 2009, 11, 2757.
10 (a) F. P. Huang, J. L. Tian, W. Gu, X. Liu, S. P. Yan, D. Z. Liao and
P. Cheng, Cryst. Growth Des., 2010, 10, 1145; (b) S. S. Chen, J. Fan,
T. Okamura, M. S. Chen, Z. Su, W. Y. Sun and N. Ueyama, Cryst.
Growth Des., 2010, 10, 812; (c) P. P. Liu, A. L. Cheng, Q. Yue, N. Liu,
W. W. Sun and E. Q. Gao, Cryst. Growth Des., 2008, 8, 1668;
(d) T. L. Hu, R. Q. Zou, J. R. Li and X. H. Bu, Dalton Trans., 2008,
1302.
11 (a) X. Q. Liang, X. H. Zhou, C. Chen, H. P. Xiao, Y. Z. Li, J. L. Zuo and
X. Z. You, Cryst. Growth Des., 2009, 9, 1041; (b) C.-P. Li, J. Chen and
M. Du, CrystEngComm, 2010, 12, 4392; (c) L.-F. Ma, C.-P. Li,
L.-Y. Wang and M. Du, Cryst. Growth Des., 2011, 11, 3309.
References
1 (a) D. J. Tranchemontagne, J. L. Mendoza-Cortés, M. O’Keeffe and
O. M. Yaghi, Chem. Soc. Rev., 2009, 38, 1257; (b) G. Férey, Chem. Soc.
Rev., 2008, 37, 191; (c) J. P. Zhang, X. C. Huang and X. M. Chen, Chem.
Soc. Rev., 2009, 38, 2385.
2 (a) L. Ma, C. Abney and W. Lin, Chem. Soc. Rev., 2009, 38, 1248;
(b) J. Y. Lee, O. K. Farha, J. Roberts, K. A. Scheidt, S. T. Nguyen and
J. T. Hupp, Chem. Soc. Rev., 2009, 38, 1450; (c) K. K. Tanabe and S.
M. Cohen, Angew. Chem., Int. Ed., 2009, 48, 7424; (d) Y. Li, P. Song,
J. Zheng and X. Li, Chem.–Eur. J., 2010, 16, 10887; (e) H. Fei,
D. L. Rogow and S. R. J. Oliver, J. Am. Chem. Soc., 2010, 132, 7202;
(f) H. Liu, Y. Liu, Y. Li, Z. Tang and H. Jiang, J. Phys. Chem. C, 2010,
114, 13362.
3 (a) S. Ma and H. C. Zhou, Chem. Commun., 2010, 46, 44; (b) J. R. Li,
R. J. Kuppler and H. C. Zhou, Chem. Soc. Rev., 2009, 38, 1477;
(c) J. B. Lin, J. P. Zhang and X. M. Chen, J. Am. Chem. Soc., 2010, 132,
6654; (d) J. Kang, S. H. Wei and Y. H. Kim, J. Am. Chem. Soc., 2010,
132, 1510; (e) L. J. Murray, M. Dinca, J. Yano, S. Chavan, S. Bordiga, C.
M. Brown and J. R. Long, J. Am. Chem. Soc., 2010, 132, 7856;
(f) Y. B. Zhang, W. X. Zhang, F. Y. Feng, J. P. Zhang and X. M. Chen,
Angew. Chem., Int. Ed., 2009, 48, 5287.
4 (a) B. Chen, L. Wang, Y. Xiao, F. R. Fronczek, M. Xue, Y. Cui and
G. Qian, Angew. Chem., Int. Ed., 2009, 48, 500; (b) K. C. Stylianou,
R. Heck, S. Y. Chong, J. Bacsa, J. T. A. Jones, Y. Z. Khimyak,
D. Bradshaw and M. J. Rosseinsky, J. Am. Chem. Soc., 2010, 132, 4119;
(c) M. D. Allendorf, C. A. Bauer, R. K. Bhakta and R. J. T. Houk, Chem.
Soc. Rev., 2009, 38, 1330; (d) X. C. Chai, Y. Q. Sun, R. Lei, Y. P. Chen,
S. Zhang, Y. N. Cao and H. H. Zhang, Cryst. Growth Des., 2010, 10,
658; (e) L. L. Liang, S. B. Ren, J. Zhang, Y. Z. Li, H. B. Du and
X. Z. You, Dalton Trans., 2010, 39, 7723.
5 (a) Z. G. Gu, Y. F. Xu, L. C. Kang, Y. Z. Li, J. L. Zuo and X. Z. You,
Inorg. Chem., 2009, 48, 5073; (b) Y. Bi, X. T. Wang, W. Liao, X. Wang,
X. Wang, H. Zhang and S. Gao, J. Am. Chem. Soc., 2009, 131, 11650;
(c) Y. Z. Tang, X. S. Wang, T. Zhou and R. G. Xiong, Cryst. Growth
Des., 2006, 6, 11; (d) D. E. Freedman, D. M. Jenkins and J. R. Long,
Chem. Commun., 2009, 4829; (e) T. W. Wang, J. Wang, S. Ohkoshi,
Y. Song and X. Z. You, Inorg. Chem., 2010, 49, 7756.
6 (a) R. Banerjee, A. Phan, B. Wang, C. Knobler, H. Furukawa,
M. O’Keeffe and O. M. Yaghi, Science, 2008, 319, 939;
(b) A. N. Khlobystov, M. T. Brett, A. J. Blake, N. R. Champness,
P. M. W. Gill, D. P. O’Neill, S. J. Teat, C. Wilson and M. Schröder,
J. Am. Chem. Soc., 2003, 125, 6753; (c) H. C. Wu, P. Thanasekaran, C.
H. Tsai, J. Y. Wu, S. M. Huang, Y. S. Wen and K. L. Lu, Inorg. Chem.,
2006, 45, 295; (d) A. Tian, J. Ying, J. Peng, J. Sha, Z. Su, H. Pang,
P. Zhang, Y. Chen, M. Zhu and Y. Shen, Cryst. Growth Des., 2010, 10,
1104.
7 (a) J. W. Cheng, S. T. Zheng and G. Y. Yang, Dalton Trans., 2007, 4059;
(b) E. Q. Gao, A. L. Cheng, Y. X. Xu, C. H. Yan and M. Y. He, Cryst.
Growth Des., 2005, 5, 1005; (c) B. C. Tzeng, T. H. Chiu, B. S. Chen and
G. H. Lee, Chem.–Eur. J., 2008, 14, 5237; (d) S. C. Chen, R. M. Yu,
Z. G. Zhao, S. M. Chen, Q. S. Zhang, X. Y. Wu, F. Wang and C. Z. Lu,
Cryst. Growth Des., 2010, 10, 1155; (e) H. L. Jiang, B. Liu and Q. Xu,
Cryst. Growth Des., 2010, 10, 806.
12 (a) B. Li, G. Li, D. Liu, Y. Peng, X. Zhou, J. Hua, Z. Shi and S. Feng,
CrystEngComm, 2011, 13, 1291; (b) B. Li, Y. Zhang, G. Li, D. Liu,
Y. Chen, W. Hu, Z. Shi and S. Feng, CrystEngComm, 2011, 13, 2457;
(c) B. Li, X. Zhou, Q. Zhou, G. Li, J. Hua, Y. Bi, Y. Li, Z. Shi and
S. Feng, CrystEngComm, 2011, 13, 4592.
13 (a) X. Duan, Y. Li, Y. Su, S. Zang, C. Zhu and Q. Meng, CrystEngComm,
2007, 9, 758; (b) J. Yang, J. F. Ma, S. R. Batten and Z. M. Su, Chem.
Commun., 2008, 2233; (c) Y. Y. Liu, J. F. Ma, J. Yang, J. C. Ma and Z.
M. Su, CrystEngComm, 2008, 10, 894; (d) J. Yao, Z. D. Lu, Y. Z. Li,
J. G. Lin, X. Y. Duan, S. Gao, Q. J. Meng and C. S. Lu, CrystEngComm,
2008, 10, 1379; (e) S. Zang, Y. Su, Y. Z. Li, J. Lin, X. Duan, Q. Meng
and S. Gao, CrystEngComm, 2009, 11, 122; (f) J. Yang, J. F. Ma, Y.
Y. Liu and S. R. Batten, CrystEngComm, 2009, 11, 151; (g) L. Wen,
Y. Li, Z. Lu, J. Lin, C. Duan and Q. Meng, Cryst. Growth Des., 2006, 6,
530; (h) Z. Tian, J. Lin, Y. Su, L. Wen, Y. Liu, H. Zhu and Q. J. Meng,
Cryst. Growth Des., 2007, 7, 1863; (i) Y. Qi, F. Luo, Y. Che and
J. Zheng, Cryst. Growth Des., 2008, 8, 606; ( j) J. Yang, J. F. Ma, Y.
Y. Liu, J. C. Ma and S. R. Batten, Cryst. Growth Des., 2008, 8, 4383;
(k) L. L. Wen, Z. D. Lu, X. M. Ren, C. Y. Duan, Q. J. Meng and S. Gao,
Cryst. Growth Des., 2009, 9, 227; (l) S. L. Li, Y. Q. Lan, J. F. Ma,
J. Yang, G. H. Wei, L. P. Zhang and Z. M. Su, Cryst.Growth Des., 2008,
8, 675; (m) H. D. Guo, X. M. Guo, S. R. Batten, J. F. Song, S. Y. Song,
S. Dang, G. L. Zheng, J. K. Tang and H. J. Zhang, Cryst. Growth Des.,
2009, 9, 1394; (n) M. H. Zeng, B. Wang, X. Y. Wang, W. X. Zhang, X.
M. Chen and S. Gao, Inorg. Chem., 2006, 45, 7069; (o) Y. Q. Lan, S.
L. Li, J. S. Qin, D. Y. Du, X. L. Wang, Z. M. Su and Q. Fu, Inorg.
Chem., 2008, 47, 10600.
14 (a) J. D. Lin, J. W. Cheng and S. W. Du, Cryst. Growth Des., 2008, 8,
3345; (b) Y. Y. Liu, J. F. Ma, J. Yang and Z. M. Su, Inorg. Chem., 2007,
46, 3027.
15 X. Z. Sun, M. H. Zeng, B. Wang, B. H. Ye and X. M. Chen, J. Mol.
Struct., 2007, 828, 10.
16 (a) N. E. Searle and R. Adams, J. Am. Chem. Soc., 1933, 55, 1649;
(b) J. F. Ma, J. F. Liu, Y. Xing, H. Q. Jia and Y. H. Lin, J. Chem. Soc.,
Dalton Trans., 2000, 2403.
2684 | Dalton Trans., 2012, 41, 2677–2684
This journal is © The Royal Society of Chemistry 2012