A Series of Rutile Networks Constructed by Dinuclear Transition Metal

Dec 16, 2009 - A Series of Rutile Networks Constructed by Dinuclear Transition Metal Units and .... Inorganic Chemistry Communications 2012 15, 130-13...
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DOI: 10.1021/cg900416v

A Series of Rutile Networks Constructed by Dinuclear Transition Metal Units and 5-Carboxyl-1-carboxymethyl-3-oxidopyridimium

2010, Vol. 10 92–98

Mei-Xiang Jiang, Cai-Hong Zhan, Yun-Long Feng,* and You-Zhao Lan Zhejiang Key Laboratory for Reactive Chemistry on Solid Surfaces, Institute of Physical Chemistry, Zhejiang Normal University, Jinhua, Zhejiang 321004, P. R. China Received April 13, 2009; Revised Manuscript Received October 31, 2009

ABSTRACT: A series of three-dimensional coordination polymers [ML(H2O)2]n (M = Mn (1), Co (2), Zn (3), Cd (4); H2L=5-carboxyl-1-carboxymethyl-3-oxidopyridimium) have been synthesized under hydrothermal conditions and characterized by single-crystal X-ray diffraction analyses, elemental analyses, IR spectra, and thermogravimetric analyses. Four complexes are isostructural and crystallize in the monoclinic system with space group P21/c. Their structures can be considered constructed from two-dimensional layers, which consist of left- and right-handed helical chains and further linked by L2ligands into three-dimensional (3D) pillared-layer frameworks. From the topological point of view, the 3D nets are binodal with three- and six-connected nodes and exhibit rutile topology. The experimental magnetic susceptibilities of 1 and 2 are interpreted with the dimer law, yielding J and g values of 1.02 cm-1, 1.99 and -0.51 cm-1, 2.32, respectively. The exchange integrals (J ) indicate weak ferromagnetic interactions between two Mn(II) ions in 1 and weak antiferromagnetic interactions between two Co(II) ions in 2. 3 and 4 exhibit intense luminescence in the solid state at room temperature.

Introduction A helix is ubiquitous in nature as well as in human art and architecture. Helicity is also present in microscopic structures such as right- or left-handed quartz1 and is widely spread in daily life and in nature. These facts have aroused more and more people’s interests to design and synthesize coordination polymers containing helices for their potential applications in the fields of adsorption, ion sensors, optical material, and asymmetric catalysis.2-9 To date, the self-assembly of helical structures is still a challenging subject to chemists for the difficulty of selection of optimal components, although a great number of coordination polymers with helical structures have been reported.10-14 According to previous literature reports,15-17 the rational design of flexible asymmetric bridging ligands is an effective method to form helical coordination polymers; Erxleben18 explored cis-pyridylethenylbenzoate to form a double helical silver coordination polymer. Hong et al.19-21 took a self-assembly reaction between metal ions and flexible twisted pyridinecarboxylate ligands to form helical frameworks. Assembly of 4-pyridylacetic acid and metal(II) ions (Zn, Cd, Mn)21 gave rise to a series of polymeric complexes, which possess a two-dimensional (2D) structure consisting of alternate left and right helical chains. With this aim in mind, we choose a new flexible asymmetric ligand, 5-carboxyl-1-carboxymethyl-3-oxidopyridimium (H2L) (Scheme 1) as a multidentate ligand to construct helical structures based on the following considerations: (a) it possesses flexibility owing to the presence of a -CH2- group between the pyridyl ring and carboxyl moiety; the skew coordination orientation of the carboxyl groups is favorable for the formation of the helical structure, and (b) the rich coordination sites and modes of the ligand provide a high likelihood for the generation of structures with high dimensions. On the basis of the aforementioned points, our aim was to synthesize novel three-dimensional (3D) helical structures by *To whom correspondence should be addressed. E-mail: [email protected]. pubs.acs.org/crystal

Published on Web 12/16/2009

Scheme 1. 5-Carboxyl-1-carboxymethyl-3-oxidopyridimium (H2L)

using a multifunctional H2L ligand. Here we report the syntheses, structures, and magnetic and luminescent properties of four novel coordination polymers of [MnL(H2O)2]n (M = Mn (1), Co (2), Zn (3), Cd (4)). The structures of 1-4 not only contain alternately left- and right-handed helical chains but also display (3,6)-connected rutile topology. Furthermore, variable temperature magnetic susceptibilities of 1 and 2, and luminescent properties of 3 and 4 at room temperature were also studied. Experimental Section Materials and General Methods. The ligand of 5-carboxyl-1carboxymethyl-3-oxidopyridimium was prepared according to the literature method.22 All other reagents were purchased commercially and used as supplied. All hydrothermal reactions were performed in a 25 mL Teflon-lined stainless steel Parr bomb. Elemental analyses were carried out using a Perkin-Elmer 2400 II elemental analyzer. IR spectra were measured in KBr pellets on a Nicolet 5DX FT-IR spectrometer. The thermogravimetric measurements were performed on preweighed samples in an oxygen stream using a Netzsch STA449C apparatus with a heating rate of 10 °C/ min. The temperature dependence of the magnetic susceptibility and magnetization of a powdered sample was measured in the presence r 2009 American Chemical Society

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Table 1. Crystal Data and Structure Refinement for 1-4 complex

1

2

3

4

empirical formula formula weight color crystal system space group a (A˚) b (A˚) c (A˚) β (°) V (A˚3) Z Dc (g 3 cm-3) μ (mm-1) F (000) θmin, θmax (°) reflections collected/uniques /Rint observed reflections (I > 2σ(I)) parameters refined S on F2 R, wR (I > 2σ(I)) R, wR (all data) max, min ΔF (e A˚-3)

C8H9MnNO7 286.10 yellow monoclinic P21/c 9.1208 (1) 10.1695(1) 11.2729(2) 109.988(1) 982.6(2) 4 1.882 1.333 580 2.32-27.59 8391/2252/0.023 2043 166 1.053 0.0279, 0.0731 0.0312, 0.0759 0.750, -0.516

C8H9CoNO7 290.09 purple monoclinic P21/c 9.0433(1) 9.9917(2) 11.2518(2) 110.645(1) 951.4(3) 4 1.908 1.725 588 2.32-27.28 7293/2150/0.0179 1989 166 1.085 0.0248, 0.0671 0.0269, 0.0684 0.379,-0.365

C8H9ZnNO7 296.53 colorless monoclinic P21/c 9.4387(1) 10.1107(1) 11.3691(1) 111.451(1) 1009.8(2) 4 1.950 2.458 600 2.79-27.44 7666/296/0.0159 2177 166 1.114 0.0540, 0.1995 0.0552, 0.2010 1.493, -1.046

C8H9CdNO7 343.56 colorless monoclinic P21/c 9.4323(1) 10.1115(1) 11.3658(1) 111.426(1) 1009.1(2) 4 2.261 2.190 672 2.32-27.44 7571/2279/0.0182 2143 166 1.023 0.0185, 0.0484 0.0201, 0.0495 0.399, -0.689

of 5 kOe from 1.9 to 300 K by a Quantum Design SQUID magnetometer on an MPMS-7 system. The excitation and luminescence spectra were obtained on a HITACHIF-2500 fluorescence spectrometer in solid state at room temperature. Synthesis of [MnL(H2O)2]n (1). MnCl2 3 4H2O (1.0 mmol, 0.1985 g), H2L (1.0 mmol, 0.1982 g), and Na2CO3 (1.0 mmol, 0.1062 g) were mixed in 15 mL of distilled water. Then the mixture was transferred into a Parr Teflon-lined stainless steel vessel (25 mL) and heated to 160 °C for 72 h. It was cooled to room temperature over 3 days. Yellow crystals of 1 were obtained and collected by filtration, washed with water, then dried in air, 72% yield (based on H2L). IR (KBr cm-1): 3317, 3060, 1619, 1572, 1480, 1389, 1340, 1314, 1053, 780, 609. Anal. Calc. for C8H9MnNO7: C, 33.55; H, 3.15; N, 4.89. Found: C, 33.52; H, 3.13; N, 4.91%. Synthesis of [CoL(H2O)2]n (2). A similar reaction of CoCl2 3 6H2O (1.0 mmol, 0.2379 g) with H2L (1.0 mmol, 0.1982 g) and Na2CO3 (1.0 mmol, 0.1062 g) in 15 mL of distilled water gave [CoL(H2O)2]n (2) as purple crystals (57% yield). IR (KBr, cm-1): 3548, 3430, 3092, 1617, 1577, 1480, 1387, 1182, 844, 732, 613. Anal. Calc. for C8H9CoNO7: C, 33.09; H, 3.10; N, 4.83. Found: C, 33.08; H, 3.08; N, 4.85%. Synthesis of [ZnL(H2O)2]n (3). A similar reaction of ZnSO4 3 2H2O (1.0 mmol, 0.2785 g) with H2L (1.0 mmol, 0.1982 g) and Na2CO3 (1.0 mmol, 0.1062 g) in 15 mL of distilled water gave [ZnL(H2O)2]n (3) as colorless crystals (32% yield). IR (KBr, cm-1): 3404, 3060, 1644, 1591, 1480, 1425, 1392, 1340, 1182, 1087, 953, 924, 864, 738. Anal. Calc. for C8H9ZnNO7: C, 32.37; H, 3.04; N, 4.72. Found: C, 32.35; H, 3.02; N, 4.68%. Synthesis of [CdL(H2O)2]n (4). A similar reaction of 3CdSO4 3 8H2O (0.33 mmol, 0.2563 g) with H2L (1.0 mmol, 0.1982 g) and Na2CO3 (1.0 mmol, 0.1062 g) in 15 mL of distilled water gave [CdL(H2O)2]n (4) as colorless crystals (65% yield). IR (KBr cm-1): 3385, 3080, 1626, 1575, 1390, 1342, 1132, 1054, 926, and 779. Anal. Calc. for C8H9CdNO7: C, 27.92; H, 2.62; N, 4.75. Found: C, 27.98; H, 2.61; N, 4.77%. Single-Crystal Structure Determination. The diffraction data for 1-4 were collected on a Bruker APXE II diffractometer equipped with a graphite-monochromatized Mo-KR radiation (λ = 0.71073 A˚) at 296(2) K. Data intensity was corrected by Lorentzpolarization factors and empirical absorption. The structures were solved by direct methods and expanded with difference Fourier techniques. All non-hydrogen atoms were refined anisotropically. Except the hydrogen atoms on oxygen atoms were located from the difference Fourier maps, the other hydrogen atoms were generated geometrically. All calculations were performed using SHELXS-97 and SHELXL-97.23,24 Basic information pertaining to crystal parameters and structure refinement are summarized in Table 1, and the selected bond lengths and bond angles are listed in Table 2.

Table 2. Selected Bond lengths (A˚) and Angles (°) for 1-4a bond

1

2

3

4

M(1)-O(3)#1 M(1)-O(1)#2 M(1)-O(1)#3 M(1)-O(5) M(1)-O(1w) M(1)-O(2w) O(3)#1-M(1)-O(1)#2 O(3)#1-M(1)-O(1W) O(1)#2-M(1)-O(1W) O(3)#1-M(1)-O(5) O(1)#2-M(1)-O(5) O(1W)-M(1)-O(5) O(3)#1-M(1)-O(1)#3 O(1)#2-M(1)-O(1)#3 O(1W)-M(1)-O(1)#3 O(5)-M(1)-O(1)#3 O(3)#1-M(1)-O(2W) O(1)#2-M(1)-O(2W) O(1W)-M(1)-O(2W) O(5)-M(1)-O(2W) O(1)#3-M(1)-O(2W) M(1)#4-O(1)-M(1)#5

2.144(1) 2.147(1) 2.258(1) 2.253(1) 2.169(1) 2.326(2) 102.15(5) 88.80(6) 167.16(5) 99.68(6) 91.98(5) 92.76(5) 175.86(6) 77.21(5) 91.38(5) 84.44(5) 80.69(7) 96.62(6) 78.36(6) 171.12(6) 95.29(6) 102.79(5)

2.109(1) 2.064(1) 2.226(1) 2.225(1) 2.077(1) 2.250(2) 102.45(5) 91.70(5) 168.46(5) 99.69(6) 90.29(5) 92.98(5) 176.40(5) 77.630(5) 87.91(6) 83.91(5) 83.46(8) 94.21(7) 81.81(7) 173.85(5) 92.94(7) 102.37(5)

2.201(5) 2.297(4) 2.328(4) 2.349(5) 2.320(5) 2.363(5) 105.35(2) 82.10(2) 160.50(2) 98.70(2) 82.94(2) 114.30(2) 176.60(2) 77.96(2) 94.56(2) 82.35(2) 96.50(2) 83.67(2) 77.50(2) 161.90(2) 83.03(2) 102.04(16)

2.202(2) 2.290(1) 2.325(1) 2.363(2) 2.317(2) 2.355(2) 105.75(6) 81.90(6) 160.42(6) 98.51(6) 82.95(5) 114.21(6) 176.51(5) 77.72(5) 94.69(6) 82.16(5) 96.76(7) 83.56(6) 77.57(7) 161.88(6) 83.20(6) 102.28(5)

a Symmetry transformations used to generate equivalent atoms: #1 x - 1, y, z; #2 -x þ 1, y - 1/2, -z þ 1/2; #3 x, -y þ 1/2, z þ 1/2; #4 -x þ 1, y þ 1/2, -z þ 1/2; #5 x, -y þ 1/2, z - 1/2. (M = Mn (1), Co (2), Zn (3), Cd (4)).

Crystallographic data for the structures reported in this paper were deposited with the Cambridge Crystallographic Data Center (CCDC nos. 721541, 741543, 714876, and 714875). Copies of available material can be obtained free of charge on application to the Director, CCDC, 12 Union Road, Cambridge CB2 1EZ, UK (Fax: þ44-1223-336033; e-mail: [email protected])

Results and Discussion Description of Structures. The single-crystal X-ray diffraction analyses showed that complexes 1-4 are isostructural and crystallize in monoclinic symmetry with space group P21/c. Therefore, only the structure of 1 is described in detail. In the asymmetrical unit of 1, there are one Mn(II) ion, one L2- ligand, and two coordinated water molecules. The Mn(II) ion is six-coordinated and has a slightly distorted octahedral coordination environment (Figure 1): two

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water molecules and four oxygen atoms from two carboxyl groups and two phenol group of four L2- ligands. The MnO distances range from 2.144(1) to 2.326(2) A˚, which are

Figure 1. Coordination environments of Mn atoms in 1. Symmetry codes for the generated atoms are the same as Table 2.

Jiang et al.

in agreement with those reported manganese complexes.25 The two carboxyl groups of the L2- ligand is fully deprotonated and coordinated with four Mn(II) ions. Two Mn(II) ions are linked by six L2- ligands to give a dimeric [Mn2L6] unit with a Mn 3 3 3 Mn distance of 3.3941(4) A˚ (Figure 5b). The dinuclear {Mn2} subunits are bridged by L2- ligands to form left- and right-handed helical chains along the b axis with the pitches of 10.1695 A˚; the adjacent helical chains are further interconnected by L2- ligands to generate a 2D sheet (Figure 2a,b). There are some examples of metal-organic coordination complexes with left- and right-handed helical chains, and most of these helix coordination polymers are alternately linked only via hydrogen bonds, π-π stacking interactions, or covalence bonds.26-31 In the title complex, the helices in the 2D layer are alternately arranged in a rightand left-handed sequence, so that the whole sheet does not show chirality. The adjacent sheets are further linked by L2ligands to give a 3D framework (Figures 3 and 4). The coordination water molecules provide additional hydrogen bonds to stabilize the crystal structure. As shown in Figure 5, each L2- ligand is linked to three dinuclear {Mn2} subunits to represent a 3-connected node (Figure 5a), and each {Mn2} subunit serves for a 6-connected node by combining six L2- ligands to result in a 6-connected node (Figure 5b); a binodal (3,6)-connected network is formed

Figure 2. (a) 2D network of 1 constructed by 1D left- and right-handed helical chains in the bc plane. (b) Space-filling diagram of the left- and right-handed helical chains in the 2D layers.

Figure 3. 3D network of 1 viewed along the approximate a (a) and b (b) axis.

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with a Schl€afli symbol of (4.62)2(42.610.83) (Figure 5c) and thus corresponds to that of rutile (rtl).32,33 The vertex symbol calculation using OLEX gives (4.62.62) for the 3-connected node and (4.4.6.6.6.6.6.6.6.6.62.62.*.*.*) for the 6-connected node. Magnetic Properties. From a magnetic point of view, both 1 and 2 can be considered as dinuclear complexes, where two metal ions are bridged by two phenolic oxygen atoms. Figure 6a

χm ¼

shows the plots of the magnetic susceptibility (χMT) vs T for 1. The experimental χMT value is 8.56 cm3 mol-1 K at room temperature and increases with decreasing temperature. This behavior is consistent with the presence of a weak ferromagnetic interaction between two Mn(II) ions.34,35 A model with a spinspin interaction Hamiltonian H=-2JS1S2 (S1=S2=5/2) combined with eq 1 was used to fit the experimental susceptibilities,

2Ng2 μ2B expð2J=kTÞ þ 5 expð6J=kTÞ þ 14 expð12J=kTÞ þ 30 expð20J=kTÞ þ 55 expð30J=kTÞ kT 3 1 þ 3 expð2J=kTÞ þ 5 expð6J=kTÞ þ 7 expð12J=kTÞ þ 9 expð20J=kTÞ þ 11 expð30J=kTÞ

where J is the exchange coupling parameter between S1 and S2, and N, g, μB, k, and T have their usual meanings. As

Figure 4. Schematic illustration of the 3D network of 1.

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ð1Þ

shown in Figure 6a, the magnetic behavior of 1 can be well reproduced by eq 1 with J = 1.02 cm-1, g = 1.99, and R (R = P 2 P [(χmT)calc - (χmT)expt] / [(χmT)expt]2) is 6.23  10-5. The magnetic susceptibility obeys the Curie-Weiss law, and a plot of 1/χM vs T yields a straight line (inset of Figure 6a) with C = 7.97 cm3 mol-1 K and θ = 7.66 K. The positive J and θ values indicate a weak ferromagnetic interaction resulting from a magnetic exchange interaction between two ions with S1 = S2 = 5/2.34,35 The ferromagnetic34-40 and antiferromagnetic38,40-49 interactions have been observed in some phenoxo-bridged dimanganese(II) complexes, where the magnetic interactions occur by superexchanging through phenoxo-oxygen atoms. For elongated octahedral Mn(II), the electronic configuration is dxy1dyz1dxz1dz21dx2-y21 in order of increase in energy. The elongation axis is taken as the z direction (along the Mn-O2W bond). Although the dz2 orbitals of the adjacent Mn(II) centers are parallel to each other and the overlap between the magnetic orbitals in the xy plane is present, the orthogonality between the dz2 orbital

Figure 5. (a) Organic 3-connected node linked with three dinuclear metal units. (b) Inorganic 6-connected dinuclear metal units coordinated with six L2- ligands. (c) Schematic representation of the rutile topology of the complex.

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Figure 6. Plot of the χMT vs T and 1/χM vs T (inset) for complexes 1 (a) and 2 (b). The solid lines result from a least-squares fit of the data to the theoretical equations.

and the other four d orbitals from two adjacent Mn(II) and the Mn-O1-Mn bond angle of 102.15(5)° reduce the overlap between the magnetic orbitals through the phenoxo bridges, and thus results in a weak ferromagnetic coupling. Figure 6b shows the plots of the magnetic susceptibility ( χMT ) vs T for 2. With a decrease of the temperature, the χMT value of 5.13 cm3 mol-1 K decreases slowly and then more rapidly at low temperature. The overall decrease in χMT with lowering temperature can be associated with the antiferromagnetic interaction among magnetic centers. A model with a spin-spin interaction Hamiltonian H = -2JS1S2 (S1=S2=3/2) combined with eq 2 was used to fit the experimental susceptibilities, 2Ng2 μ2B χm ¼ kT 3 expð2J=kTÞ þ 5 expð6J=kTÞ þ 14 expð12J=kTÞ 1 þ 3 expð2J=kTÞ þ 5 expð6J=kTÞ þ 7 expð12J=kTÞ ð2Þ The best fit gives J = -0.51 cm-1, g = 2.32, and R = 3.86  10-5. The magnetic susceptibility for 2 also fits the CurieWeiss law with C = 5.15 cm3 mol-1 K and θ = -5.46 K (inset of Figure 6b). The negative J and θ values suggest an antiferromagnetic interaction between the Co(II) centers. The electronic configuration of the octahedral Co(II) is dxy1dyz1dxz1 with dz2 and dx2-y2 orbitals empty. Although the overlap between the two empty orbitals and the occupied orbitals of two adjacent Co(II) ions favors a ferromagnetic coupling, the strong overlap between the magnetic orbitals [(dxz)(dyz)(dxy)] through the phenoxo bridges conducts to a weak antiferromagnetic superexchange. Such antiferromagnetic interaction between the Co(II) ions has been observed in some phenoxo-bridged Co(II) compounds.50-54 Apart from the antiferromagnetic exchange between the Co(II) centers, the spin-orbit coupling for Co(II) ions with a 4T1g ground state in an octahedral field may be contribute to such magnetic behavior.52 The precise calculation of the magnetic interactions not only requires reliable values of ligand-field and spin orbital coupling parameters, but also of the degree of electron delocalization, so some literature reports treated such cases merely as an empirical term to estimate.51-54 Photoluminescent Properties. The d10 metal compounds have been reported to exhibit interesting photoluminescent properties.55-59 The solid-state luminescent properties of H2L and complexes 3 and 4 were investigated at room temperature, and their emission spectra are given in Figure 7. Complex 3 shows blue fluorescent with a broadband mainly

Figure 7. Photoluminescent spectra of H2L and complexes 3 and 4 in the solid state at room temperature.

ranging from 425 to 450 nm, and the maximum emission wavelength is at 439 nm upon photoexcitation at 366 nm. Complex 4 displays a strong purple fluorescent emission with maximum at 385 nm. In comparison with H2L ligand that displays a weak fluorescent emission with a maximum at 564 nm. The maximum emission bands of 3 and 4 are a large blue-shift shift. The emissions of complexes 3 and 4 may be attributed to the π-π* electronic transition (see quantum chemistry analysis below) of the ligand.60,61 The enhancement of luminescence in the coordination may be attributed to the rigidity of them. The coordination enhances the “rigidity” of the ligand and thus reduces the loss of energy through a radiationless pathway. To further identify the type of charge transfer, we perform the first principle calculations using density functional theory in the generalized gradient approximation (GGA) of Perdew, Burke and Ernzerhof,62 as implemented in the DMol3 program Materials Studio 4.0.63 The core treatment of all electron and all electron relativistic were separately used for Zn- and Cd-complexes (i.e., 3 and 4) with double numerical plus d-functions atomic basis set.64 The other parameters and convergent criterions were set by the default values of the DMol3 program. In general, the charge transfer between the frontier molecular orbitals, such as the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) makes a significant contribution to the low-lying excited transition of system. The HOMO and LUMO of 3 and 4 at Γ point are given in

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Figure 8. HOMO and LUMO of 3 and 4.

References

Figure 9. TG curve of complex 1.

Figure 8, from which we can assign the emission peak to the intraligand (π-π*) fluorescent emission.65 Note that the π orbital is a partially bonding orbital, while the π* orbital is a completely antibonding orbital. Thermal Analyses. Since 1-4 are isomorphic, complex 1 is taken as an example to explain the thermal stability. The TG curve of complex 1 exhibits two well-separated weight loss stages (Figure 9). The weight loss from 115 to 175 °C corresponds to the release of the coordinated water molecule. The observed weight loss of 12.47% is consistent with the calculated value of 12.50%. The second step is from 272 to 325 °C, and the organic ligands were burnt. The final residuals are MnO. Conclusion In summary, four novel 3D coordination polymers with left- and right-handed helical chains have been synthesized by hydrothermal reactions of transition metal salts and the multifunctional 5-carboxyl-1-carboxymethyl-3-oxidopyridimium ligand. The frameworks display (3,6)-connected rutile topology. Weak ferromagnetic interaction between the Mn(II) ions of 1 was found with J = 1.02 cm-1, g = 1.99 and antiferromagnetic interaction between the Co(II) ions with J = -0.51 cm-1, g = 2.32. 3 and 4 exhibit intense photoluminescence in solid state at room temperature. Since these condensed materials are highly thermally stable, colorless, and insoluble in common polar and nonpolar solvents, they may be good candidates for potential photoactive materials. Acknowledgment. The authors gratefully thank Prof. Dr. B.-Z. Lin at Huaqiao University for the guidance in analyses of the magnetic properties and the Natural Sciences Foundation of Zhejiang Province for financial support of the project (No. Y406355).

(1) Jung, J. H.; Ono, Y.; Shinkai, S. Chem.;Eur. J. 2000, 6, 4552. (2) Chen, B. L.; Ma, S. Q.; Hurtado, E. J.; Lobkovsky, E. B.; Zhou, H. C. Inorg. Chem. 2007, 46, 8490. (3) Chen, B. L.; Ma, S. Q.; Zapata, F.; Fronczek, F. R.; Lobkovsky, E. B.; Zhou, H. C. Inorg. Chem. 2007, 46, 1233. (4) Chen, B. L.; Yang, Y.; Zapata, F.; Qian, G. D.; Luo, Y. S.; Zhang, J. H.; Lobkovsky, E. B. Inorg. Chem. 2006, 45, 8882. (5) Wang, X. L.; Qin, C.; Wang, E. B.; Su, Z. M. Chem.;Eur. J. 2006, 12, 2680. (6) Evans, O. R.; Lin, W. Acc. Chem. Res. 2002, 35, 511. (7) Yaghi, O. M.; O’Keeffe, M.; Ockwig, N. W.; Chae, H. K.; Eddaoudi, M.; Kim, J. Nature 2003, 423, 705. (8) Kitagawa, S.; Kitaura, R.; Noro, S. I. Angew. Chem., Int. Ed. 2004, 43, 2334. (9) Swiegers, G. F.; Malefetse, T. J. Chem. Rev. 2000, 100, 3483. (10) Zhou, Y. F.; Jiang, F. L.; Xu, Y.; Cao, R.; Hong, M. C. J. Mol. Struct. 2004, 691, 191. (11) Zang, S. Q.; Su, Y.; Li, Y. Z.; Ni, Z. P.; Meng, Q. J. Inorg. Chem. 2006, 45, 174. (12) Zhang, S.; Cao, Y. N.; Zhang, H. H.; Chai, X. C.; Chen, Y. P. J. Solid State Chem. 2008, 181, 399. (13) Chen, X. D.; Mak, T. C. W. J. Chem. Soc., Dalton Trans. 2005, 3646. (14) Wang, Y. T.; Tong, M. L.; Fan, H. H.; Wang, H. Z.; Chen, X. M. J. Chem. Soc., Dalton Trans. 2005, 424. (15) Banfi, S.; Carlucci, L.; Caruso, E.; Ciani, G.; Proserpio, D. M. J. Chem. Soc., Dalton Trans. 2002, 2714. (16) Tong, M. L.; Chen, X. M.; Ye, B. H.; Ng, S. W. Inorg. Chem. 1998, 37, 5278. (17) Su, C. Y.; Cai, Y. P.; Chen, C. L.; Lissner, F.; Kang, B. S.; Kaim, W. Angew. Chem., Int. Ed. 2002, 41, 3371. (18) Erxleben, A. Inorg. Chem. 2001, 40, 2928. (19) Zhao, Y. J.; Hong, M. C.; Sun, D. F.; Cao, R. J. Chem. Soc., Dalton Trans. 2002, 1354. (20) Zhao, Y. J.; Hong, M. C.; Sun, D. F.; Cao, R. Inorg. Chem. 2002, 5, 565. (21) Li, X.; Cao, R.; Sun, Y. Q.; Shi, Q.; Yuan, D. Q.; Sun, D. F.; Bi, W. H.; Hong, M. C. Cryst. Growth Des. 2004, 4, 255. (22) Bao, M.; Liu, B. D.; Ning, Z. G. J. Northeast Normal Univ. 1994, 2, 50. (23) Sheldrick, G. M. SHELXS-97, Program for X-ray Crystal Structure Solution; University of G€ottingen: G€ottingen, Germany, 1997. (24) Sheldrick, G. M. SHELXL-97, Program for X-Ray Crystal Structure Refinement; University of G€ottingen: G€ottingen, Germany, 1997. (25) Devereux, M.; McCann, M.; Leon, V.; McKee, K.; Ball, R. J. Polyhedron 2002, 21, 1063. (26) Qi, Y. J.; Wang, Y. H.; Hu, C. W.; Cao, M. H.; Mao, L.; Wang, E. B. Inorg. Chem. 2003, 42, 8519. (27) Xu, L.; Qin, C.; Wang, X. L.; Wei, Y. G.; Wang, E. B. Inorg. Chem. 2003, 42, 7342. (28) Chen, X. M.; Liu, G. F. Chem.;Eur. J. 2002, 8, 4811. (29) Du, M.; Li, C. P.; Zhao, X. J. Cryst.Growth Des. 2006, 6, 335. (30) Wang, Y.; Ding, B.; Cheng, P.; Liao, D. Z.; Yan, S. P. Inorg. Chem. 2007, 46, 2002. (31) Liu, N.; Yue, Q.; Wang, Y. Q.; Cheng, A. L.; Gao, E. Q. J. Chem. Soc., Dalton Trans. 2008, 4621. (32) Blatov, V. A.; Carlucci, L.; Ciani, G.; Proserpio, D. M. CrystEngComm 2004, 6, 378. (33) Cao, X. Y.; Zhang, J.; Li, Z. J.; Cheng, J. K.; Yao, Y. G. CrystEngComm 2007, 9, 806. (34) Chang, H.-R.; Larsen, S.-K.; Poyd, P. D. W.; Pierpont, C. G.; Hendrickson, D. N. J. Am. Chem. Soc. 1988, 110, 4565.

98

Crystal Growth & Design, Vol. 10, No. 1, 2010

(35) Lambert, S. L.; Hendrickson, D. N. Inorg. Chem. 1979, 18, 2683. (36) Mikuriya, M.; Nakadera, K.; Tokii, T. Inorg. Chim. Acta 1992, 194, 129. (37) Luneau, D.; Savariault, J.-M.; Cassoux, P.; Tuchagues, J.-P. J. Chem. Soc., Dalton Trans. 1988, 1225. (38) Koizumi, S.; Nihei, M.; Oshio, H. Chem. Lett. 2004, 33, 896. (39) Chang, H.-R.; Larsen, S.-K.; Boyd, P. D. W.; Pierpont, C. G.; Hendrickson, D. N. J. Am. Chem. Soc. 1988, 110, 4565. (40) Aono, T.; Wada, H.; Yonemura, M.; Ohba, M.; Okawa, H.; Fenton, D. E. J. Chem. Soc., Dalton Trans. 1997, 1527. (41) Coucouvanis, D.; Greiwe, K.; Salifoglou, A.; Challen, P.; Simopoulos, A.; Kostikas, A. Inorg. Chem. 1988, 27, 593. (42) Bartlett, R. A.; Ellison, J. J.; Power, P. P.; Shoner, S. C. Inorg. Chem. 1991, 30, 2888. (43) Jones, R. A.; Koschmeider, S. U.; Nunn, C. M. Inorg. Chem. 1988, 27, 4524. (44) Hodgson, D. J.; Schwartz, B. J.; Sorrell, T. N. Inorg. Chem. 1989, 28, 2226. (45) Kessissoglow, D. P.; Butler, W. M.; Pecoraro, V. L. Inorg. Chem. 1987, 26, 495. (46) Sakiyama, H.; Tokuyama, K.; Matsumura, Y.; Okawa, H. J. Chem. Soc., Dalton Trans. 1993, 2329. (47) Qian, M.; Gou, S.; Chantrapromma, S.; Sundara, S. S. R.; Fun, H.-K.; Zeng, Q.; Yu, Z.; You, X. Inorg. Chim. Acta 2000, 305, 83. (48) Gultneh, Y.; Farooq, A.; Liu, S.; Karlin, K. D.; Zubieta, J. Inorg. Chem. 1992, 31, 3607. (49) Qian, M.; Gou, S.; Yu, Z.; Ju, H.; Xu, Y.; Duan, C.; You, X. Inorg. Chim. Acta 2001, 317, 157. (50) Mukherjee, A.; Lloret, F.; Mukherjee, R. Inorg. Chem. 2008, 47, 4471.

Jiang et al. (51) Tian, J.; Gu, W.; Yan, S.; Liao, D.; Jiang, Z. Z. Anorg. Allg. Chem. 2008, 1775. (52) Black, D.; Blake, A. J.; Dancey, K. P.; Harrison, A.; McPartlin, M.; Parsons, S.; Tasker, P. A.; Whittaker, G.; Schr€ oder, M. J. Chem. Soc., Dalton Trans. 1998, 3953. (53) Singh, R.; Banerjee, A.; Gordon, Y.; Rajak, K. K. Transition Met. Chem. 2009, 34, 689. (54) Rodrıguez, L.; Labisbal, E.; Sousa-Pedrares, A; Garcıa-Vazquez, J. A.; Romero, J.; Duran, M. L.; Real, J. A.; Sousa, A. Inorg. Chem. 2006, 45, 7903. (55) Choi, D. H.; Yoon, J. H.; Lim, J. H.; Kim, H. C.; Hong, C. S. Inorg. Chem. 2006, 45, 5947. (56) Hong, M. C.; Zhao, Y. J.; Su, W. P.; Cao, R.; Fujita, M.; Zhou, Z. Y.; Chan, A. S. C. Angew. Chem., Int. Ed. 2000, 39, 2468. (57) Yang, E. C.; Zhao, H. K.; Ding, B.; Wang, X. G.; Zhao, X. J. Cryst. Growth. Des. 2007, 7, 2009. (58) Wang, X. W.; Chen, J. Z.; Liu, J. H. Cryst. Growth. Des. 2007, 7, 1227. (59) He, Y. H.; Feng, Y. L.; Lan, Y. Z.; Wen, Y. H. Cryst. Growth Des. 2008, 8, 3586. (60) Yang, F.; Ren, Y. X.; Li, D. S.; Fu, F.; Qi, G. C.; Wang, Y. Y. J. Mol. Struct. 2008, 892, 283. (61) Roy, P.; Manassero, M.; Dhara, K.; Banerjee, P. Polyhedron 2009, 28, 1133. (62) Perdew, J. P.; Burke, K.; Ernzerhof, M. Phys. Rev. Lett. 1996, 77, 3865. (63) Accelrys, Materials Studio Getting Started, Release 4.0; Accelrys Software, Inc.: San Diego, 2006. (64) Delley, B. J. Chem. Phys. 1990, 92, 508. (65) Wen, L. L.; Dang, D. B.; Duan, C. Y.; Li, Y. Z.; Tian, Z. F.; Meng, Q. J. Inorg. Chem. 2005, 44, 7161.