English

• 1. INTRODUCTION

  Crystalline materials,such as coordination polymers (CPs)/metal-organic frameworks(MOFs)^[1] and covalent organic frameworks (COFs)^[2],have recei-ved great attention recently,not only because of their charming topological networks^[3],but also due to their extensiveapplications in gas storage and selective separation^[4],protonconductors^[5],and heterogeneous catalysis^[6]. In the past decade,many studies are focused on the use of rigid aromatic polycarboxylate ligands in constructing functional MOFs due to their various coordination modes to metal ions,which would promote the structural diversity and construct intriguing topological net-works^[7]. Recently,using the azolate-carboxylate bifunctional organic ligands in constructing novel functional coordination polymers has received much attention on account of their multi-connectivity abilities^[8] andinteresting magnetic^[9],gas adsorp-tion^[10] and fluorescence properties^[11].1H-1,2,4-triazole and its derivatives have been proven to be good organic linkers in the construction of versatile MOFs due to their potential μ_1,2- , μ_2,4- and μ_1,2,4- bridging fashions^[12]. Furthermore,the employment of mixed bifunctional organic ligands and 1H-1,2,4-triazole derivatives may construct interesting topo-logies. In this work,we aimed to investigate the effect of introducing the second ligand 3-amino-1,2,4-triazolate (Hatrz) on the coordination behavior ofthe primary ligand 4-(4-carboxyphen-yl)-1,2,4-triazole (Hcpt) (Scheme 1) . As expected,we obtained two new zinc(II)complexes [Zn(cpt)(OH)]n·nH₂O (FJU-32) and [Zn(cpt)(atrz)]n (FJU-33) with different topologies. For FJU-32,ZnII iscoordinated to three μ₃-OH groups forming novel 1D zigzag double chains,which are connected to four neighbouring double chains by the cpt ligands to form an extended 3D porous coordination polymer. And for FJU-33,Zn ions are first bridged by atrz anions to give 2D [Zn(atrz)] layers,which are further pillared by the cpt ligands through Zn-O coordination bonds and hydrogen-bonding interac-tions between the amino groups from atrz with triazole from cpt to produce a 3D architecture. In the absence of Hatrz,both the carbonxylate O and triazole N atoms from the cpt ligand in FJU-32 can bind Zn atoms,while in the presence of Hatrz,only itscarbonxylate O atom in FJU-33 can do. The neutron triazole group of the cpt ligand has weaker coordination ability than the triazolate anion of atrz ligand. In addition,the thermal stability and lumine-scent property of FJU-32 and FJU-33 have also been investigated.

  Figure Scheme 1

  

  Figure Scheme 1.  Schematic diagram forthe synthesis of two novel zinc(II) complexes based on bifunctional ligands and controlling the second ligands

  DownLoad: Full-Size Img PowerPoint

  2. EXPERIMENTAL

  2.1. Materials and methods

  The organic ligand Hcpt synthesis followed the method previously reported by our group^[10a]. Other reagents and solventsused in synthetic studies were commercially available and used as supplied without further purification. Elemental analyses (C,H,N) were determined with an Elementar Vario EL III microanalyzer. The Fourier transforminfrared (KBr pellets) spectra were recorded in the range of 400～4000 cm^-1 on a Thermo Nicolet 5700 FT-IR instru-ments. Powder X-ray diffraction (PXRD) was carried out with a PANalytical X’Pert3 powder diffractometer equipped with a Cu sealed tube (λ =1.541874 Å) at 40 kV and 40 mA over the 2θ range of 5～ 30°. The simulated pattern was produced using the Mercury V1.4 program and single-crystal diffraction data. Thermal analysis was carried out on a METTLER TGA/SDTA 851 thermal analyzer from 30 to 600 ℃ at a heating rate of 10 ℃···min^-1 under N₂ flow. Solid-state fluorescence spectra were carried out on a HORIBADual-FL-800 fluorescence spectrometer with a 150 W xenon lamp as light source at room temperature.

  2.2. Synthesis of [Zn(cpt)(OH)]n·nH₂O (FJU-32)

  A solution of Hcpt (19.0 mg,0.1 mmol) in DMF (5 mL) containing triethylamine (28 μL,2 mmol) was directly mixed with a solution of ZnCl₂ in water (1 mL,0.10 mol·L^-1) atroom temperature; after-wards,ethanol(2 mL) was added. The resulted solu-tion was transferred and sealed in a 23 mL Teflon-lined stainless-steel reactor,and heated at 85 ℃ for 72 h. The resulting pale yellow crystals were collected,washed with EtOH and dried at room temperature. Yield 55% (based on Hcpt). Elemental analysis calcd. (%) for C₉H₉N₃O₄Zn: C,37.64; N,14.56; H,3.14. Found: C,37.28; N,14.84; H,3.27. IR (KBr pellet,cm^-1): 3735 (w),3521(s),3459 (s),3064 (s),1610 (s),1544 (s),1407 (s),1317 (m),1249 (m),1101(w),773 (m).

  2.3. Synthesis of [Zn(cpt)(atrz)]n (FJU-33)

  A mixture of Zn(NO₃) 2·6H₂O (29.2 mg,0.1 mmol),Hcpt (19.3 mg,0.1 mmol),Hatrz (8.5 mg,0.1 mmol),2 mL DMF and 2 mL H₂O in a 20 mL vial was heated at 80 ℃ for 2 days,and then cooled to room temperature,obtaining colorlessbulk crystals of FJU-33.Yield 52% (based on Hcpt). Elemental analysis calcd. (%) for C11H9N7O2Zn: C,39.25; N,29.13; H,2.69. Found (%): C,38.85; N,28.74; H,2.58. IR (KBr pellet,cm^-1): 3735 (w),3394(s),3313 (m),3120 (m),1623 (s),1525(s),1371(s),1303(m),1228(m),1085(m),860(w),779 (s).

  2.4. Crystal structure determination and refinement

  Data collection and structural analysis of single crystals FJU-32 and FJU-33 were collected on an Agilent Technologies SuperNova single crystal diffractometer equipped with graphite-monochro-matic Mo-Kα or Cu-Kα radiation (λ= 0.71073 and 1.54184 Å). The crystal was kept at 293(2) K during data collection. Using Olex2^[13],the structure was solved with the Superflip^[14] structure solution program with charge flipping and refined with the ShelXL^[15] refinement package using least-squares minimization. All non-hydrogen atoms were refined with anisotropic displacement parameters.The hydrogen atoms on theligands were placed inideali-zed positions and refined using a riding model. The selected bond lengths and bond angles are given in Tables 1 and 2,respectively. Hydrogen-bonding interaction parameters for FJU-33 are shown in Table 3.

  Table 1

  

  Table 1.  Selected Bond Lengths (Å) and Bond Angles (°) forFJU-32

  DownLoad: CSV

  Bond	Dist.	Bond	Dist.	Bond	Dist.
  Zn(1) -O(3) #2	2.008(4)	Zn(1) -O(3) #3	2.184(4)	O(3) -Zn(1) #5	2.008(4)
  Zn(1) -O(3)	2.022(4)	O(2) -Zn(1) #4	2.072(4)	O(3) -Zn(1) #3	2.185(4)
  Zn(1) -N(2)	2.039(5)	Zn(1) -O(2) #1	2.072(4)
  Angle	(°)	Angle	(°)	Angle	(°)
  O(3) #3-Zn(1) -O(3)	136.5(2)	O(3) -Zn(1) -O(3) #2	80.10(16)	Zn(1) #5-O(3) -Zn(1)	136.5(2)
  O(3) #3-Zn(1) -N(2)	109.25(18)	N(2) -Zn(1) -O(3) #2	93.32(17)	Zn(1) #5-O(3) -Zn(1) #2	99.90(16)
  O(3) -Zn(1) -N(2)	110.17(18)	O(2) #1-Zn(1) -O(3) #2	157.37(16)	Zn(1) -O(3) -Zn(1) #2	99.96(16)
  O(3) #3-Zn(1) -O(2) #1	89.78(16)	N(2) -Zn(1) -O(2) #1	109.16(18)	O(3) #2-Zn(1) -O(3) #3	80.10(16)
  O(3) -Zn(1) -O(2) #1	94.09(16)
  Symmetry transformation: #1: -x,-1/2+y,1/2-z; #2: -1+x,y,z; #3: 1-x,1-y,1-z,#4: -x,1/2+y,1/2-z; #5: 1+x,y,z

  Table 2

  

  Table 2.  Selected Bond Lengths (Å) and Bond Angles (°) forFJU-33

  DownLoad: CSV

  Angle (°) Angle (°) Angle (°) O(1) -Zn(1) -N(6) 125.04(16) O(1) -Zn(1) -N(5) 101.62(14) N(6) -Zn(1) -N(5) 108.33(13)

  Bond	Dist.	Bond	Dist.	Bond	Dist.
  Zn(1) -O(1) Zn(1) -N(7)	1.968(3) 2.021(3)	Zn(1) -N(6)	1.992(3)	Zn(1) -N(5)	2.009(3)
  O(1) -Zn(1) -N(7)	100.58(14)	N(6) -Zn(1) -N(7)	108.27(14)	N(5) -Zn(1) -N(7)	112.83(15)

  Table 3

  

  Table 3.  Hydrogen Bond Lengths (Å) and Bond Angles (°) for FJU-33

  DownLoad: CSV

  D-H···A	d (D-H)	d (H···A)	∠DHA	d (D···A)
  N(4) -H(4B)···N(2) #3	0.86	2.372	119.3	2.893(6)
  N(4) -H(4A)···N(1) #3	0.86	2.492	115.6	2.967(7)
  Symmetry transformation:#3: -x,1-y,1-z

  Figure 1

  

  Figure 1.  (a) Coordination environment of Zn(II)in [Zn(cpt)(OH)]n·nH₂O(FJU-32) (symmetry codes:#1 = -x,-0.5+y,0.5-z; #2 = 1-x,1-y,1-z；#3 = -1+x,y,z；#4 = 2-x,1-y,1-z；#5 = 1+x,1.5-y,0.5+z; #6 = -x,1-y,1-z; #7 = x,1.5-y,0.5+z); (b) The extended 1D ZnO zigzag double chains along the aaxis;(c) View of the 3D framework of FJU-32 along the aaxis; (d) Topologicalrepresentation of the pcunets in FJU-32.Guests and H atoms are omitted for clarity. Zn,N,O and C atoms are shown as sky blue,blue,red and gray spheres,respectively

  DownLoad: Full-Size Img PowerPoint

  3. RESULTS AND DISCUSSION

  3.1. Structure description

  A single-crystal X-ray diffraction analysis reveals that FJU-32 crystallizes in the monoclinic space group P2₁/c. The asymmetric unit of FJU-32 contains one crystallographically independent zinc cation,one cpt ligand,one μ₃-OH groupand one H₂O as guest. As shown in Fig. 1a,Zn(1) is coor-dinated to four O atoms from three μ₃-OH groups and one carboxylate group of cpt ligand,and one N atom from another cpt ligand to generate a distortion trigonal bipyramidal coordination environment. The Zn-O bond lengths (2.010(4) ～2.189(4) Å) are all within the normal ranges^[16]. It should be noted that the two ZnO zigzag single chains are connected through Zn-O bonds to form an unprecedented extended 1Dribbon-like double-chain structure along the a axis (Fig. 1b). The 1D double chains are connected to four neighbouring double chains by the cpt ligands to form an extended 3D porous coordination network (Fig. 1c). For the sake of clarity,if we simplify the adjacent two Zn atoms as six-connected nodes,FJU-32 adopts the pcu net topology^{[17, 18]} with the Schlflipoint symbol {4¹².6³} (Fig. 1d)^[19].

  Figure 2

  

  Figure 2.  (a) Local coordination environment of Zn(II) ions in [Zn(cpt)(atrz)]n (FJU-33) . All hydrogen atoms were omitted for clarity (Symmetry codes: #1 = 1-x,1-y,-z; #2 = 1-x,0.5+y,0.5-z; #3 = -x,1-y,1-z); 2Dlayer structures (b) and topological (4.8²) net (c) of FJU-33. The red oxygen atoms presentthe cpt ligands; (d) 3D suparmolecular framework constructed by interlayer hydrogen-bonding interactions; (e) 4-Connected sra topological net of the 3D framework FJU-33 (considering the interlayer hydrogen-bonding interactions). Zn,N,O,C and H atoms are shown as sky blue,blue,red,gray and green spheres,respectively

  DownLoad: Full-Size Img PowerPoint

  The crystallographic analysis reveals that FJU-33 crystallizesin the monoclinic P2₁/c space group. The asymmetric unit consists of one uniqueZn(II) atom,one atrz ligand and one cpt ligand. The Zn(II) ion adopts a distorted tetrahedron coordination environment,whichis completed by three nitrogen atoms from three different atrz ligands and one oxygen atom affordedby the monodentate cpt ligand (Fig. 2a). The Zn-N distances range from 1.992(3) to 2.021(3) Å,and the Zn-O distance of 1.968(3) Å. Each atrz ligand binds to three Zn atoms,resulting in a two-dimensional (2D) layer with 4.82 topology (Fig. 2b~c)^[20]. It is worth noting that the cpt ligands via the Zn-O coordinated bonds stand on each side of [Zn(atrz)] plane to balance the 2D layer’ charge. The uncoordinated N atoms from cpt ligands form thehydrogen-bonding interactions with neighboring layers uncoordinated amino groups (d [N(4) (-NH₂ )···N(2) (cpt)] = 2.893(6) Å; d [N(4) (-NH₂) ···N(1) (cpt)] = 2.967(7) Å) (Table 3) ,which has significant impact on connecting the neighboring layers to generate a 3D supramoleculararchitectures (Fig. 2d). When the four-coordinated Zn(II) centers and the atrz ligands are regarded as similar distorted tetrahedral nodes,the resultant 3D frameworks could be described as a four-connected sra topology with Schlfli symbol of (42.63.8) ,which is related to the structural prototype of zeolite ABW (or SrAl2) (Fig. 2e)^[21].

  3.2. Powder X-ray diffraction

  The as-synthesized samples of FJU-32 and FJU-33 have been characterized by powder X-ray diffraction (PXRD) (Fig. 3) . The experimental PXRD pattern corresponds well with the simulated pattern of the single crystal data,indicating the pure phase of the as-synthesized samples.

  Figure 3

  

  Figure 3.  Powder X-ray diffraction patterns of FJU-32(a) and FJU-33 (b)

  DownLoad: Full-Size Img PowerPoint

  3.3. Thermogravimetric analysis and luminescent properties

  In order to examine the thermal stabilities of the as-synthesized samples,thermal gravimetric analy-ses (TGA) were carried out in the temperature range of 30～600 ℃ under N₂ atmosphere. As shown in Fig. 4,the TGA curve for FJU-32 shows a total weight loss of 6.31% between 30 and 120℃,which corresponds to the loss of one guest water molecule (calcd: 6.23%),and the structure begins to collapse when heating upon to 302 ℃. The TGA result indicated that FJU-33 showed high thermal stability up to 330 ℃ . After that,the whole framework began to collapse.

  Figure 4

  

  Figure 4.  TGAcurves for FJU-32 and FJU-33

  DownLoad: Full-Size Img PowerPoint

  Figure 5

  

  Figure 5.  Luminescence emission spectra forFJU-32,FJU-33 and Hcpt

  DownLoad: Full-Size Img PowerPoint

  Considering the FJU-32 and FJU-33 are typical d¹⁰ transition-metal configuration^[22],the photolu-minescence experiments were performed at room temperature in the solid state. Excitation of FJU-32 and FJU-33 in the solid state at 430 and 380 nm resulted in luminescent emission peaks at 530 and 426 nm (Fig. 5) ,respectively. The Hcpt and Hatrz ligands show an emissionpeak at 434 nm (λ_ex = 360 nm) and 411 nm (λ_ex = 325 nm),respectively^[22],which is probably caused by the π*-nor π*-π transi-tion^[23]. When compared to the photoluminescence spectrum of the free Hcpt ligand,the emission band of FJU-32 is red-shifted by 96 nm,which comes fromthe ligand-to-metal charge transfer (LMCT)^[24]. It’s worth noting that FJU-33 displays the blue and red shifts of ca.8 and15 nm relative to thefree Hcpt and Hatrz ligands,which illustrates the metal-to-ligand (MLCT) and ligand-to-metal charge-transfer (LMCT) co exist in FJU-33. The solid-state fluore-scence reveals that FJU-32 and FJU-33 are potential optical materials.

  4. CONCLUSION

  In summary,throughsolvothermal reaction,we have synthesized two novel coordination polymers based on bifunctional organic ligands Hcpt and Zn(II) salts,and demonstratedthat the first ligands Hcpt coordination properties are related to the second ligands Hatrz. Compared with the 4-substituted 1,2,4-triazole group of Hcpt,the atrz anions in FJU-33 have stronger coordination ability. Furthermore,FJU-32 and FJU-33 dis play high thermal stability up to 300 ℃,and the result of the solid-state fluorescence reveals that two new complexes are potential optical materials.

• 1. [1]

     (a) Zhou, H. C.; Long, J. R.; Yaghi, O. M. Introduction to metal-organic frameworks. Chem. Rev. 2012, 112, 673-674; (b) Sato, H.; Kosaka, W.; Matsuda, R.; Hori, A.; Hijikata, Y.; Belosludov, R. V.; Sakaki, S.; Takata, M.; Kitagawa, S. Self-accelerating CO sorption in a soft nanoporous crystal. Science 2014, 343, 167-170; (c) Férey, G.; Serre, C. Large breathing effects in three-dimensional porous hybrid matter: facts, analyses, rules and consequences. Chem. Soc. Rev. 2009, 38, 1380-1399.

  2. [2]

     El-Kaderi H. M, Hunt J. R, Mendoza-Cortés J. L, C?té A. P, Taylor R. E, O’Keeffe M, Yaghi O. M. Designed synthesis of 3D covalent organic frameworks[J]. Science, 2007, 316:  268-272. doi: 10.1126/science.1139915

  3. [3]

     (a) O’Keeffe, M.; Yaghi, O. M. Deconstructing the crystal structures of metal-organic frameworks and related materials into their underlying nets. Chem. Rev. 2012, 112, 675-702; (b) Guillerm, V.; Kim, D.; Eubank, J. F.; Luebke, R.; Liu, X.; Adil, K.; Lah, M. S.; Eddaoudi, M. A supermolecular building approach for the design and construction of metal-organic frameworks. Chem. Soc. Rev. 2014, 43, 6141-6172.

  4. [4]

     (a) Xiang, S. C.; Zhang, Z. J.; Zhao, C. G.; Hong, K.; Zhao, X.; Ding, D. R.; Xie, M. H.; Wu, C. D.; Das, M. C.; Gill, R.; Thomas, K. M.; Chen, B. L. Rationally tuned micropores within enantiopure metal-organic frameworks for highly selective separation of acetylene and ethylene. Nat. Commun. 2011, 2, 204-210; (b) Xiang, S. C.; He, Y. B.; Zhang, Z. J.; Wu, H.; Zhou, W.; Krishna, R.; Chen, B. L. Microporous metal-organic framework with potential for carbon dioxide capture at ambient conditions. Nat. Commun. 2012, 3, 954-962; (c) Zhang, Z.; Yao, Z. Z.; Xiang, S.; Chen, B. Perspective of microporous metal-organic frameworks for CO2 capture and separation. Energy Environ. Sci. 2014, 7, 2868-2899; (d) Shen, Y. C.; Li, Z. Y.; Wang, L. H.; Ye, Y. X.; Liu, Q.; Ma, X. L.; Chen, Q. H.; Zhang, Z. J.; Xiang, S. C. Cobalt-citrate framework armored with graphene oxide exhibiting improved thermal stability and selectivity for biogas decarburization. J. Mater. Chem. A 2015, 3, 593-599; (e) Chen, Y.; Li, Z. Y.; Liu, Q.; Shen, Y. C.; Wu, X. Z.; Xu, D. D.; Ma, X. L.; Wang, L. H.; Chen, Q. H.; Zhang, Z. J.; Xiang, S. C. Microporous metal-organic framework with lantern-like dodecanuclear metal coordination cages as nodes for selective adsorption of C2/C1 mixtures and sensing of nitrobenzen. Cryst. Growth Des. 2015, 15, 3847-3852; (f) Liu, L. Z.; Ye, Y. X.; Yao, Z. Z.; Zhang, L. Q.; Li, Z. Y.; Wang, L. H.; Ma, X. L.; Chen, Q. H.; Zhang, Z. J.; Xiang, S. C. A hierarchically porous metal-organic framework from semirigid ligand for gas adsorption. Chin. J. Chem. 2016, 34, 215-219; (g) Yao, Z.; Zhang, Z.; Liu, L.; Li, Z.; Zhou, W.; Zhao, Y.; Han, Y.; Chen, B.; Krishna, R.; Xiang, S. Extraordinary separation of acetylene-containing mixtures with microporous metal-organic frameworks with open O donor sites and tunable robustness through control of the helical chain secondary building units. Chem.-Eur. J. 2016, 22, 5676-5683; (h) Song, C.; Jiao, J.; Lin, Q.; Liu, H.; He, Y. C2H2 adsorption in three isostructural metal-organic frameworks: boosting C2H2 uptake by rational arrangement of nitrogen sites. Dalton Trans. 2016, 45, 4563-4569.

  5. [5]

     (a) Ramaswamy, P.; Wong, N. E.; Shimizu, G. K. H. MOFs as proton conductors-challenges and opportunities. Chem. Soc. Rev. 2014, 43, 5913-5932; (b) Xu, G.; Otsubo, K.; Yamada, T.; Sakaida, S.; Kitagawa, H. Superprotonic conductivity in a highly oriented crystalline metal-organic framework nanofilm. J. Am. Chem. Soc. 2013, 135, 7438-7441; (c) Ye, Y.; Zhang, L.; Peng, Q.; Wang, G. E.; Shen, Y.; Li, Z.; Wang, L.; Ma, X.; Chen, Q. H.; Zhang, Z.; Xiang, S. High anhydrous proton conductivity of imidazole-loaded mesoporous polyimides over a wide range from subzero to moderate temperature. J. Am. Chem. Soc. 2015, 137, 913-918; (d) Su, X.; Yao, Z.; Ye, Y.; Zeng, H.; Xu, G.; Wu, L.; Ma, X.; Chen, Q. H.; Wang, L.; Zhang, Z.; Xiang, S. 40-Fold enhanced intrinsic proton conductivity in coordination polymers with the same proton-conducting pathway by tuning metal cation nodes. Inorg. Chem. 2016, 55, 983-986; (e) Ye, Y.; Wu, X.; Yao, Z.; Wu, L.; Cai, Z.; Wang, L.; Ma, X.; Chen, Q. H.; Zhang, Z.; Xiang, S. Metal-organic frameworks with large breathing effect to host hydroxyl compounds for high anhydrous proton conductivity over a wide temperature range from subzero to 125 ℃. J. Mater. Chem. A 2016, 4, 4062-4070.

  6. [6]

     Liu J, Chen L, Cui H, Zhang J, Zhang L, Su C. Y. Applications of metal-organic frameworks in heterogeneous supramolecular catalysis[J]. Chem. Soc. Rev., 2014, 43:  6011-6061. doi: 10.1039/C4CS00094C

  7. [7]

     He Y, Li B, O'Keeffe M, Chen B. Multifunctional metal-organic frameworks constructed from meta-benzenedicarboxylate units[J]. Chem. Soc. Rev., 2014, 43:  5618-5656. doi: 10.1039/C4CS00041B

  8. [8]

     (a) Xue, D. X.; Cairns, A. J.; Belmabkhout, Y.; Wojtas, L.; Liu, Y.; Alkordi, M. H.; Eddaoudi, M. Tunable rare-earth fcu-MOFs: a platform for systematic enhancement of CO2 adsorption energetics and uptake. J. Am. Chem. Soc. 2013, 135, 7660-7667; (b) He, C. T.; Tian, J. Y.; Liu, S. Y.; Ouyang, G.; Zhang, J. P.; Chen, X. M. A porous coordination framework for highly sensitive and selective solid-phase microextraction of non-polar volatile organic compounds. Chem. Sci. 2013, 4, 351-356.

  9. [9]

     (a) Savard, D.; Lin, P. H.; Burchell, T. J.; Korobkov, I.; Wernsdorfer, W.; Clérac, R.; Murugesu, M. Two-dimensional networks of lanthanide cubane-shaped dumbbells. Inorg. Chem. 2009, 48, 11748-11754; (b) Aharen, T.; Habib, F.; Korobkov, I.; Burchell, T. J.; Guillet-Nicolas, R.; Kleiz, F.; Murugesu, M. Novel Co-based metal-organic frameworks and their magnetic properties using asymmetrically binding 4-(4?-carboxyphenyl)-1,2,4-triazole. Dalton Trans. 2013, 42, 7795-7802; (c) Holmberg, R. J.; Kay, M.; Korobkov, I.; Kadantsev, E.; Boyd, P. G.; Aharen, T.; Desgreniers, S.; Woo, T. K.; Murugesu, M. An unprecedented CoII cuboctahedron as the secondary building unit in a Co-based metal-organic framework. Chem. Commun. 2014, 50, 5333-5335.

  10. [10]

      (a) Ye, Y. X.; Xiong, S. S.; Wu, X. N.; Zhang, L. Q.; Li, Z. Y.; Wang, L. H.; Ma, X. L.; Chen, Q. H.; Zhang, Z. J.; Xiang, S. C. Microporous metal-organic framework stabilized by balanced multiple host-counter anion hydrogen-bonding interactions for high-density CO2 capture at ambient conditions. Inorg. Chem. 2016, 55, 292-299; (b) Chen, D. M.; Ma, J. G.; Cheng, P. Solvent-induced secondary building unit (SBU) variations in a series of Cu(II) metal-organic frameworks derived from a bifunctional ligand. Dalton Trans. 2015, 44, 8926-8931; (c) Chen, D. M.; Zhang, X. P.; Shi, W.; Cheng, P. Microporous metal-organic framework based on a bifunctional linker for selective sorption of CO2 over N₂ and CH4. Inorg. Chem. 2015, 54, 5512-5518; (d) Chen, D. M.; Tian, J. Y.; Fang, S. M.; Liu, C. S. Two isomeric Zn(II)-based metal-organic frameworks constructed from a bifunctional triazolate-carboxylate tecton exhibiting distinct gas sorption behaviors. CrystEngComm. 2016, 18, 2579-2584.

  11. [11]

      (a) Song, J. F.; Zhou, R. S.; Zhang, J.; Xu, C. Y.; Li, Y. B.; Wang, B. B. Three new cpt-metal complexes displaying 0D, 1D, and 3D topology structures. Z. Anorg. Allg. Chem. 2011, 637, 589-595; (b) Wang, L.; Ye, Y.; Zhang, L.; Chen, Q.; Ma, X.; Zhang, Z.; Xiang, S. A 3D-diamond-like metal-organic framework: crystal structure, nonlinear optical effect and high thermal stability. Inorg. Chem. Commun. 2015, 60, 19-22; (c) Yang, L. B.; Wang, H. C.; Fang, X. D.; Chen, S. J.; Xu, Q. Q.; Zhu, A. X.; Yang, Z. A series of Zn(II) and Cd(II) coordination compounds based on 4-(4H-1,2,4-triazol-4-yl) benzoic acid: synthesis, structure and photoluminescence properties. CrystEngComm. 2016, 18, 130-142.

  12. [12]

      (a) Zhang, J. P.; Zhang, Y. B.; Lin, J. B.; Chen, X. M. Metal azolate frameworks: from crystal engineering to functional materials. Chem. Rev. 2012, 112, 1001-1033; (b) Huang, C.; Ji, F.; Liu, L.; Li, N.; Li, H.; Wu, J.; Hou, H.; Fan, Y. Seven dicarboxylate-based coordination polymers with structural varieties and different solvent resistance properties derived from the introduction of small organic linkers. CrystEngComm. 2014, 16, 2615-2625.

  13. [13]

      Dolomanov A. V, Bourhis L. J, Gildea R. J, Howard J. A. K, Puschmann H. OLEX2: a complete structure solution refinement and analysis program. J[J]. Appl. Crystallogr., 2009, 42:  339-341. doi: 10.1107/S0021889808042726

  14. [14]

      Palatinus L, Chapuis G. SUPERFLIP-a computer program for the solution of crystal structures by charge flipping in arbitrary dimensions. J[J]. Appl. Crystallogr., 2007, 40:  786-790. doi: 10.1107/S0021889807029238

  15. [15]

      Sheldrick G. M. A short history of SHELX. Acta Crystallogr[J]. Sect. A: Found. Crystallogr., 2008, :  .

  16. [16]

      (a) Ling, Y.; Yang, F.; Deng, M.; Chen, Z.; Liu, X.; Weng, L.; Zhou, Y. Novel iso-reticular Zn(ii) metal-organic frameworks constructed by trinuclear-triangular and paddle-wheel units: synthesis, structure and gas adsorption. Dalton Trans. 2012, 41, 4007-4011; (b) Su, Z.; Bai, Z. S.; Fan, J.; Xu, J.; Sun, W. Y. Synthesis and characterization of 3d-3d homo- and heterometallic coordination polymers with mixed ligands. Cryst. Growth Des. 2009, 9, 5190-5196.

  17. [17]

      Delgado-Friedrichs O, O’Keeffe M. Identification of and symmetry computation for crystal nets[J]. Acta Crystallogr., 2003, :  .

  18. [18]

      Jiang Z. Q, Jiang G. Y, Wang F, Zhao Z, Zhang J. Controlling state of breathing of two isoreticular microporous metal-organic frameworks with triazole homologues[J]. Chem.-Eur. J., 2012, 18:  10525-10529. doi: 10.1002/chem.v18.34

  19. [19]

      Blatov, V. A.; Shevchenko, A. P.; Proserpio, D. M. Applied topological analysis of crystal structures with the program package ToposPro. Cryst. G r o w t h D e s . 2 0 1 4 , 1 4 , 3 5 7 6 - 3 5 8 6 .

  20. [20]

      Song Z, Gao H, Li G, Yu Y, Shi Z, Feng S. Influence of noncovalent intermolecular interactions on crystal packing: syntheses and crystal structures of three layered Zn(II)/1,2,4-triazole/carboxylate coordination polymers[J]. CrystEngComm., 2009, 11:  1579-1584. doi: 10.1039/b901445d

  21. [21]

      (a) Jia, L. N.; Hou, L.; Wei, L.; Jing, X. J.; Liu, B.; Wang, Y. Y.; Shi, Q. Z. Five sra topological Ln(III)-MOFs based on novel metal-carboxylate/Cl chain: structure, near-infrared luminescence and magnetic properties. Cryst. Growth Des. 2013, 13, 1570-1576; (b) Huang, S. Y.; Li, J. Q.; Wu, X. L.; Zhang, X. M.; Luo, M. B.; Luo, F. A new acrylamide MOF with sra net showing an uncommon eight-fold interpenetration. Inorg. Chem. Commun. 2014, 44, 29-31.

  22. [22]

      Gao J, Wang N, Xiong X, Chen C, Xie W, Ran X, Long Y, Yue S, Liu Y. Syntheses, structures, and photoluminescent properties of a series of zinc(II)-3-amino-1,2,4-triazolate coordination polymers constructed by varying carboxylate anions[J]. CrystEngComm., 2013, 15:  3261-3270. doi: 10.1039/c3ce00049d

  23. [23]

      (a) He, K. H.; Li, Y. W.; Chen, Y. Q.; Song, W. C.; Bu, X. H. Employing zinc clusters as SBUs to construct (3,8) and (3,14)-connected coordination networks: structures, topologies, and luminescence. Cryst. Growth Des. 2012, 12, 2730-2735; (b) Li, L. J.; Qin, C.; Wang, X. L.; Shao, K. Z.; Su, Z. M.; Liu, P. J. Synthesis and characterization of two self-catenated networks and one case of pcu topology based on the mixed ligands. CrystEngComm. 2012, 14, 4205-4209.

  24. [24]

      Cui Y, Yue Y, Qian G, Chen B. L. Luminescent functional metal-organic frameworks[J]. Chem. Rev., 2012, 112:  1126-1162. doi: 10.1021/cr200101d

• 

  Scheme 1  Schematic diagram forthe synthesis of two novel zinc(II) complexes based on bifunctional ligands and controlling the second ligands

  下载: 全尺寸图片 幻灯片
  

  Figure 1  (a) Coordination environment of Zn(II)in [Zn(cpt)(OH)]n·nH₂O(FJU-32) (symmetry codes:#1 = -x,-0.5+y,0.5-z; #2 = 1-x,1-y,1-z；#3 = -1+x,y,z；#4 = 2-x,1-y,1-z；#5 = 1+x,1.5-y,0.5+z; #6 = -x,1-y,1-z; #7 = x,1.5-y,0.5+z); (b) The extended 1D ZnO zigzag double chains along the aaxis;(c) View of the 3D framework of FJU-32 along the aaxis; (d) Topologicalrepresentation of the pcunets in FJU-32.Guests and H atoms are omitted for clarity. Zn,N,O and C atoms are shown as sky blue,blue,red and gray spheres,respectively

  下载: 全尺寸图片 幻灯片
  

  Figure 2  (a) Local coordination environment of Zn(II) ions in [Zn(cpt)(atrz)]n (FJU-33) . All hydrogen atoms were omitted for clarity (Symmetry codes: #1 = 1-x,1-y,-z; #2 = 1-x,0.5+y,0.5-z; #3 = -x,1-y,1-z); 2Dlayer structures (b) and topological (4.8²) net (c) of FJU-33. The red oxygen atoms presentthe cpt ligands; (d) 3D suparmolecular framework constructed by interlayer hydrogen-bonding interactions; (e) 4-Connected sra topological net of the 3D framework FJU-33 (considering the interlayer hydrogen-bonding interactions). Zn,N,O,C and H atoms are shown as sky blue,blue,red,gray and green spheres,respectively

  下载: 全尺寸图片 幻灯片
  

  Figure 3  Powder X-ray diffraction patterns of FJU-32(a) and FJU-33 (b)

  下载: 全尺寸图片 幻灯片
  

  Figure 4  TGAcurves for FJU-32 and FJU-33

  下载: 全尺寸图片 幻灯片
  

  Figure 5  Luminescence emission spectra forFJU-32,FJU-33 and Hcpt

  下载: 全尺寸图片 幻灯片

  Table 1.  Selected Bond Lengths (Å) and Bond Angles (°) forFJU-32

  Bond	Dist.	Bond	Dist.	Bond	Dist.
  Zn(1) -O(3) #2	2.008(4)	Zn(1) -O(3) #3	2.184(4)	O(3) -Zn(1) #5	2.008(4)
  Zn(1) -O(3)	2.022(4)	O(2) -Zn(1) #4	2.072(4)	O(3) -Zn(1) #3	2.185(4)
  Zn(1) -N(2)	2.039(5)	Zn(1) -O(2) #1	2.072(4)
  Angle	(°)	Angle	(°)	Angle	(°)
  O(3) #3-Zn(1) -O(3)	136.5(2)	O(3) -Zn(1) -O(3) #2	80.10(16)	Zn(1) #5-O(3) -Zn(1)	136.5(2)
  O(3) #3-Zn(1) -N(2)	109.25(18)	N(2) -Zn(1) -O(3) #2	93.32(17)	Zn(1) #5-O(3) -Zn(1) #2	99.90(16)
  O(3) -Zn(1) -N(2)	110.17(18)	O(2) #1-Zn(1) -O(3) #2	157.37(16)	Zn(1) -O(3) -Zn(1) #2	99.96(16)
  O(3) #3-Zn(1) -O(2) #1	89.78(16)	N(2) -Zn(1) -O(2) #1	109.16(18)	O(3) #2-Zn(1) -O(3) #3	80.10(16)
  O(3) -Zn(1) -O(2) #1	94.09(16)
  Symmetry transformation: #1: -x,-1/2+y,1/2-z; #2: -1+x,y,z; #3: 1-x,1-y,1-z,#4: -x,1/2+y,1/2-z; #5: 1+x,y,z

  下载: 导出CSV

  Table 2.  Selected Bond Lengths (Å) and Bond Angles (°) forFJU-33

  Angle (°) Angle (°) Angle (°) O(1) -Zn(1) -N(6) 125.04(16) O(1) -Zn(1) -N(5) 101.62(14) N(6) -Zn(1) -N(5) 108.33(13)

  Bond	Dist.	Bond	Dist.	Bond	Dist.
  Zn(1) -O(1) Zn(1) -N(7)	1.968(3) 2.021(3)	Zn(1) -N(6)	1.992(3)	Zn(1) -N(5)	2.009(3)
  O(1) -Zn(1) -N(7)	100.58(14)	N(6) -Zn(1) -N(7)	108.27(14)	N(5) -Zn(1) -N(7)	112.83(15)

  下载: 导出CSV

  Table 3.  Hydrogen Bond Lengths (Å) and Bond Angles (°) for FJU-33

  D-H···A	d (D-H)	d (H···A)	∠DHA	d (D···A)
  N(4) -H(4B)···N(2) #3	0.86	2.372	119.3	2.893(6)
  N(4) -H(4A)···N(1) #3	0.86	2.492	115.6	2.967(7)
  Symmetry transformation:#3: -x,1-y,1-z

  下载: 导出CSV
•