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Structure tuning in amino-functionalized coordination polymers based on different V-shaped dicarboxylate ligands
Inorganic Chemistry Communications 73 (2016) 183–186
Contents lists available at ScienceDirect
Inorganic Chemistry Communications journal homepage: www.elsevier.com/locate/inoche
Structure tuning in amino-functionalized coordination polymers based on different V-shaped dicarboxylate ligands Yongbing Lou ⁎, Yinglian Peng, Xin Zhang, Jinxi Chen ⁎ School of Chemistry and Chemical Engineering, Southeast University, Nanjing 211189, PR China
a r t i c l e
i n f o
Article history: Received 13 September 2016 Received in revised form 14 October 2016 Accepted 16 October 2016 Available online 18 October 2016 Keywords: Coordination polymer Crystal structure Amino-functionalized Zn(II) compound
a b s t r a c t Two flexible V-shaped dicarboxylate coligands (H2IBG = isophthaloylbisglycine, and H2PPDA = 4,4′(perfluoropropane-2,2-diyl)dibenzoic acid) were selected to construct two new amino-functionalized coordination polymers based on Zn salt and a rigid linear ligand L (L = 3,6-di(3-imidazolyl)benzene-1,2-diamine. Both {[Zn(PPDA)(L)]·3H2O}n (1) and {[Zn2(IBG)(L)]·2H2O}n (2) were crystallized in mononuclear structure. Complex 1 shows a 3-D super structure based on ABAB packing, while complex 2 shows a 2-D layered structure. Structural diversity was acquired due to the flexibility of dicarboxylate ligands. Crystallographic and spectroscopic properties of both complexes were explored. © 2016 Elsevier B.V. All rights reserved.
Coordination polymers (CPs) or metal-organic frameworks (MOFs) have been heavily explored due to their various fascinating structures and numerous possible applications in gas adsorption [1–3], separation [4–6], heterogeneous catalysis [7,8], chemical and fluorescence sensing [9–11]. Incorporation of polar functional groups, such as alkylamines and heterocycle aromatic amines, into CPs has been widely investigated to improve catalytic property, fluorescence property, gas absorption selectivity, and so on [12–22]. Employment of polycarboxylate ligands in the preparation of CPs is of particular interest because they are effective linkers to bridge the inorganic units [12,23–25]. We have utilized Vshaped ligand bis(4-(pyridine-4-yl)phenyl)amine and different rigid dicarboxylate ligands to construct CPs in our previous work [26]. In order to further investigate the effect of V-shaped dicarboxylate ligands on their complex structures, herein we use a nitrogen containing rigid linear ligand L (L = 3,6-di(3-imidazolyl)benzene-1,2-diamine and two different V-shaped dicarboxylate coligands (H2IBG = isophthaloylbisglycine, and H2PPDA = 4,4′-(perfluoropropane-2,2diyl)dibenzoic acid) to construct two new amino-functionalized CPs ({[Zn(PPDA)(L)]·3H2O}n (1) and {[Zn2(IBG)(L)]·2H2O}n (2)) (see Scheme 1 for the preparation scheme and ESI for detailed preparation procedures). Various coordination modes of carboxylates in each coligand are responsible for the structure differentiation in these two complexes. In addition, thermogravimetric analyses and fluorescence properties of both complexes were also investigated. Complex 1 crystallizes in a monoclinic system with P21/c space group and packs into a 3-D superstructure by ABAB stacking of 2-D planar structures. The coordination environment of the Zn(II) ion in the ⁎ Corresponding authors. E-mail addresses: [email protected] (Y. Lou), [email protected] (J. Chen).
http://dx.doi.org/10.1016/j.inoche.2016.10.028 1387-7003/© 2016 Elsevier B.V. All rights reserved.
secondary building unit (SBU) is shown in Fig. 1a. The Zn(II) ion is five-coordinated by two nitrogen atoms and three oxygen atoms, where two oxygen atoms are from one carboxylate and one is from the other carboxylate of two PPDA2− anions. Two nitrogen atoms are from imidazolyl groups in two different L ligands. The bond length of Zn\\O is in the range 2.000(4)–2.404(5) Å and the bond length of Zn\\N is in the range 2.003(4)–2.033(4) Å. The bond angle for N\\Zn\\N is 108.62(18)°. The bond angles for O\\Zn\\O and O\\Zn\\N are in the range 57.73(18)–120.17(18)°, 91.66(18)–155.35(18)°, respectively. 1-D zig-zag chains are formed in between PPDA2− ions and Zn(II) ions while these chains were connected by L ligands to form a 2-D layered structure (Fig. 1b). These layered structures were packed into 3-D superstructure through an ABAB packing sequences (Fig. 1c and d). There exist two different types of pores (rectangular pore A and pore B) in the final superstructure of complex 1. The dimension of the larger rectangular pore A is around 7.2 × 6.5 Å2, and the dimension of the smaller pore B is around 3.6 × 1.8 Å2. The topology for complex 1 was analyzed in detail by using the TOPOS program. The Zn centers can be regarded as 4-connected nodes, where L and PPDA2− ligands are acting as linkers. Thus, the whole structure can thus be represented as a sql net (Fig. S1, in ESI). Complex 2 crystallizes in a monoclinic system with C2/c space group. The asymmetric unit of 2 includes two crystallographically independent Zn2+ cations (Zn1 and Zn2), one ligand L, one IBG2− anion, and two water molecules, which were removed by the SQUEEZE routine in PLATON (Fig. 2a). Zn1 forms a tetrahedral structure coordinating with two N atoms and two O atoms, where two N atoms are from two independent L ligands and two O atoms are from two independent IBG2− anions. Zn2 has a similar coordination mode with Zn1 except that the bonding length and bonding angles are different. The bond lengths of
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Scheme 1. Synthetic scheme for the preparation of two complexes.
Zn1\\O and Zn1\\N are 1.950(4) Å and 1.972(4) Å. The bond angles of O\\Zn1\\O and N\\Zn1\\N are 105.2(2)° and 102.6(2)°, while the bond angle of O\\Zn1\\N is in the range 104.1(2)°–121.0(2)°. In comparison, the bond length of Zn2\\O is 1.973(4) Å and the bond length of Zn2\\N is in the range 2.016(8)–2.105(8) Å. The bond angles of O\\Zn2\\O and N\\Zn2\\N are 118.2(2)° and 81.2(5)°, while the bond angle of O\\Zn2\\N is in the range 99.4(3)°–128.0(3)°. Zn2+ cations are connected by IBG2− anions to form two linear chain structures as illustrated in red and blue color in Fig. 2b and c. These two linear chains are linked together by ligand L to from a 2-D planar structure with Zn2+ cation as the symmetric center. These planar structures are packed into layered super structure as shown in Fig. 2d. Due to the disorder of imidazole, the topology for complex 2 was analyzed by Diamond program. The Zn centers can be treated as 4-connected nodes, where L and IBG2− ligands are acting as linkers. Thus, the whole structure can thus be represented as a sql net (Fig. S2, in ESI). The abundant
hydrogen bonds in complexes 1 and 2 are presented in detail in Table S1 and Table S2 (in ESI), respectively. Due to hydrogen bond interactions, adjacent 2D layers of complexes 1 and 2 all are further packed into three-dimensional (3D) supramolecular frameworks. Powder X-ray diffraction analyses were carried out to confirm the purities of complexes 1 and 2, while the experimental data of both complexes are nearly consistent with their simulated data (Fig. S3 and S4, in ESI). It indicates that both complexes are successfully prepared as pure crystalline. Thermogravimetric analyses (TGA) were carried out in nitrogen atmosphere to examine the thermal stabilities of these complexes (Fig. 3). For complex 1, the weight loss of 7.12% in the range 20–280 °C is due to the loss of three lattice water molecules (calcd 7.20%), while after the temperature reaching 400 °C the complex 1 starts to decompose rapidly. For complex 2, the loss of two lattice water molecules before 200 °C gives a weight loss of 5.16% (calcd 5.41%). Then above 300 °C, the network of complex 2 starts to collapse
Fig. 1. (a) Coordination environment of the Zn(II) ions in complex 1. The hydrogen atoms and solvent molecules are omitted for clarity. Symmetry codes: #1 = x, −1 + y, z, #2 = 1 + x, y, z; (b) A view of the 2-D network; (c) The ABAB packing of two layered structures; (d) 3-D structure of complex 1 showing two types of mesopores A and B.
Y. Lou et al. / Inorganic Chemistry Communications 73 (2016) 183–186
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Fig. 2. (a) Coordination environment of the Zn(II) ions in complex 2. The hydrogen atoms and solvent molecules are omitted for clarity. Symmetry codes: # 1 = 2 − x, y, 2.5 − z, # 2 = 3 − x, y, 1.5 − z, # 3 = 1 + x, −y, 0.5 + z, # 4 = 2 − x, −y, 2 − z; (b) and (c) 2-D layers along c and b axes; (d) 2-D layered super structure of complex 2.
gradually. Complex 1 is more stable thermally than that of complex 2, which is probably due to the high stability of 3-D super structure based on ABAB packing of 2-D layers in complex 1. Luminescent microporous CPs constructed with d10 metal centers and conjugated organic linkers are promising candidates for applications as fluorescent sensors [11,27–29]. The solid-state luminescence properties of free ligand L, H2PPDA, H2IBG, complexes 1 and 2 are investigated at room temperature (Fig. 4). The fluorescent emission band of ligand L is occurred at 376 nm (λex = 286 nm), while H2PPDA shows emission band at 326 nm (λex = 280 nm) and H2IBG shows emission band at 446 nm (λex = 303 nm), respectively. These ligand emissions bands may be assigned to the π* → π or π* → n electronic transitions. Complex 1 shows two emission bands around 450 nm and 480 nm (λex = 286 nm) while complex 2 shows two emission bands around 445 nm and 480 nm (λex = 270 nm). Both complexes show same emission band around 480 nm, which is ascribed to the intra-ligand transition from ligand L. There is a red-shift of ~ 100 nm in comparison to
Fig. 3. TGA curves of complexes 1 and 2.
ligand L emission, which is due to the deprotonation and the stabilization of π* orbitals of ligand L by the electron withdrawing effect of the metal ion as commonly seen in d10 centered complexes [30–33]. The shoulder emission band around 486 nm in complex 1 is ascribed to the intraband transition of ligand PPDA2 −, where the red shift is due to the deprotonation and electron withdrawing effect of the metal ion [31–33]. The shoulder emission around 445 nm in complex 2 is ascribed to intra-ligand emission from IBG2−, where the deprotonation of H2IBG will not affect benzene π orbitals and there exists no direct interaction from metal ion with benzene π orbitals due to the spatial separation by methylene group. These two new complexes may be good candidates for novel hybrid inorganic-organic photoactive materials. In summary, two new amino-functionalized compounds were successfully prepared and characterized by the self-assembly of linear ligand L, V-shaped dicarboxylate ligands and Zn(II) salts under similar
Fig. 4. Solid-state photoluminescence spectra of L, H2PPDA, H2IBG, complexes 1 and 2 at room temperature and the excitation spectra of complexes 1 and 2.
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condition. These complexes exhibited interesting structural diversities due to the different flexibility of dicarboxylate ligands. The strong interaction between the ligand and metal ion is one of the important factors for the red-shift of ligand based emission seen in both complexes. Acknowledgements The authors would like to express thanks to Jiangsu Provincial Financial Support of Fundamental Conditions and Science and Technology for People's Livelihood for Jiangsu Key Laboratory of Advanced Metallic Materials (BM2007204), the National Natural Science Foundation of China (21475021, 21427807), the Natural Science Foundation of Jiangsu Province (BK20141331) and the Fundamental Research Funds for the Central Universities (2242016K40083). Appendix A. Supplementary material CCDC 1496053(1) and 1496054(2) contain the supplementary crystallographic data for this paper. Copies of the data can be obtained free of charge via bwww.ccdc.cam.ac.uk/conts/retrieving.htmlN, or from the Cambridge Crystallographic Data Centre, 12, Union Road, Cambridge, CB2 1EZ, U.K.; fax: +44 1223 336033; or email: [email protected]. uk. Detailed materials and physical measurements, additional powder X-ray diffraction spectra, topology drawings and single X-ray diffraction analyses are available as electronic supplementary information in the online version, at 10.1016/j.inoche.2016.10.028. References [1] Y. He, W. Zhou, G. Qian, B. Chen, Methane storage in metal-organic frameworks, Chem. Soc. Rev. 43 (2014) 5657–5678. [2] M.P. Suh, H.J. Park, T.K. Prasad, D.W. Lim, Hydrogen storage in metal-organic frameworks, Chem. Rev. 112 (2012) 782–835. [3] R.B. Getman, Y.S. Bae, C.E. Wilmer, R.Q. Snurr, Review and analysis of molecular simulations of methane, hydrogen, and acetylene storage in metal-organic frameworks, Chem. Rev. 112 (2012) 703–723. [4] H. Sato, W. Kosaka, R. Matsuda, A. Hori, Y. Hijikata, R.V. Belosludov, S. Sakaki, M. Takata, S. Kitagawa, Self-accelerating CO sorption in a soft nanoporous crystal, Science 343 (2014) 167–170. [5] S. Qiu, M. Xue, G. Zhu, Metal-organic framework membranes: from synthesis to separation application, Chem. Soc. Rev. 43 (2014) 6116–6140. [6] J.R. Li, J. Sculley, H.C. Zhou, Metal-organic frameworks for separations, Chem. Rev. 112 (2012) 869–932. [7] J. Liu, L. Chen, H. Cui, J. Zhang, L. Zhang, C.Y. Su, Applications of metal-organic frameworks in heterogeneous supramolecular catalysis, Chem. Soc. Rev. 43 (2014) 6011–6061. [8] M. Yoon, R. Srirambalaji, K. Kim, Homochiral metal-organic frameworks for asymmetric heterogeneous catalysis, Chem. Rev. 112 (2012) 1196–1231. [9] L.E. Kreno, K. Leong, O.K. Farha, M. Allendorf, R.P. Van Duyne, J.T. Hupp, Metal-organic framework materials as chemical sensors, Chem. Rev. 112 (2012) 1105–1125. [10] Z. Hu, B.J. Deibert, J. Li, Luminescent metal-organic frameworks for chemical sensing and explosive detection, Chem. Soc. Rev. 43 (2014) 5815–5840. [11] O.S. Wenger, Vapochromism in organometallic and coordination complexes: chemical sensors for volatile organic compounds, Chem. Rev. 113 (2013) 3686–3733. [12] W. Lu, Z. Wei, Z.Y. Gu, T.F. Liu, J. Park, J. Park, J. Tian, M. Zhang, Q. Zhang, T. Gentle 3rd, M. Bosch, H.C. Zhou, Tuning the structure and function of metal-organic frameworks via linker design, Chem. Soc. Rev. 43 (2014) 5561–5593.
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Contents lists available at ScienceDirect
Inorganic Chemistry Communications journal homepage: www.elsevier.com/locate/inoche
Structure tuning in amino-functionalized coordination polymers based on different V-shaped dicarboxylate ligands Yongbing Lou ⁎, Yinglian Peng, Xin Zhang, Jinxi Chen ⁎ School of Chemistry and Chemical Engineering, Southeast University, Nanjing 211189, PR China
a r t i c l e
i n f o
Article history: Received 13 September 2016 Received in revised form 14 October 2016 Accepted 16 October 2016 Available online 18 October 2016 Keywords: Coordination polymer Crystal structure Amino-functionalized Zn(II) compound
a b s t r a c t Two flexible V-shaped dicarboxylate coligands (H2IBG = isophthaloylbisglycine, and H2PPDA = 4,4′(perfluoropropane-2,2-diyl)dibenzoic acid) were selected to construct two new amino-functionalized coordination polymers based on Zn salt and a rigid linear ligand L (L = 3,6-di(3-imidazolyl)benzene-1,2-diamine. Both {[Zn(PPDA)(L)]·3H2O}n (1) and {[Zn2(IBG)(L)]·2H2O}n (2) were crystallized in mononuclear structure. Complex 1 shows a 3-D super structure based on ABAB packing, while complex 2 shows a 2-D layered structure. Structural diversity was acquired due to the flexibility of dicarboxylate ligands. Crystallographic and spectroscopic properties of both complexes were explored. © 2016 Elsevier B.V. All rights reserved.
Coordination polymers (CPs) or metal-organic frameworks (MOFs) have been heavily explored due to their various fascinating structures and numerous possible applications in gas adsorption [1–3], separation [4–6], heterogeneous catalysis [7,8], chemical and fluorescence sensing [9–11]. Incorporation of polar functional groups, such as alkylamines and heterocycle aromatic amines, into CPs has been widely investigated to improve catalytic property, fluorescence property, gas absorption selectivity, and so on [12–22]. Employment of polycarboxylate ligands in the preparation of CPs is of particular interest because they are effective linkers to bridge the inorganic units [12,23–25]. We have utilized Vshaped ligand bis(4-(pyridine-4-yl)phenyl)amine and different rigid dicarboxylate ligands to construct CPs in our previous work [26]. In order to further investigate the effect of V-shaped dicarboxylate ligands on their complex structures, herein we use a nitrogen containing rigid linear ligand L (L = 3,6-di(3-imidazolyl)benzene-1,2-diamine and two different V-shaped dicarboxylate coligands (H2IBG = isophthaloylbisglycine, and H2PPDA = 4,4′-(perfluoropropane-2,2diyl)dibenzoic acid) to construct two new amino-functionalized CPs ({[Zn(PPDA)(L)]·3H2O}n (1) and {[Zn2(IBG)(L)]·2H2O}n (2)) (see Scheme 1 for the preparation scheme and ESI for detailed preparation procedures). Various coordination modes of carboxylates in each coligand are responsible for the structure differentiation in these two complexes. In addition, thermogravimetric analyses and fluorescence properties of both complexes were also investigated. Complex 1 crystallizes in a monoclinic system with P21/c space group and packs into a 3-D superstructure by ABAB stacking of 2-D planar structures. The coordination environment of the Zn(II) ion in the ⁎ Corresponding authors. E-mail addresses: [email protected] (Y. Lou), [email protected] (J. Chen).
http://dx.doi.org/10.1016/j.inoche.2016.10.028 1387-7003/© 2016 Elsevier B.V. All rights reserved.
secondary building unit (SBU) is shown in Fig. 1a. The Zn(II) ion is five-coordinated by two nitrogen atoms and three oxygen atoms, where two oxygen atoms are from one carboxylate and one is from the other carboxylate of two PPDA2− anions. Two nitrogen atoms are from imidazolyl groups in two different L ligands. The bond length of Zn\\O is in the range 2.000(4)–2.404(5) Å and the bond length of Zn\\N is in the range 2.003(4)–2.033(4) Å. The bond angle for N\\Zn\\N is 108.62(18)°. The bond angles for O\\Zn\\O and O\\Zn\\N are in the range 57.73(18)–120.17(18)°, 91.66(18)–155.35(18)°, respectively. 1-D zig-zag chains are formed in between PPDA2− ions and Zn(II) ions while these chains were connected by L ligands to form a 2-D layered structure (Fig. 1b). These layered structures were packed into 3-D superstructure through an ABAB packing sequences (Fig. 1c and d). There exist two different types of pores (rectangular pore A and pore B) in the final superstructure of complex 1. The dimension of the larger rectangular pore A is around 7.2 × 6.5 Å2, and the dimension of the smaller pore B is around 3.6 × 1.8 Å2. The topology for complex 1 was analyzed in detail by using the TOPOS program. The Zn centers can be regarded as 4-connected nodes, where L and PPDA2− ligands are acting as linkers. Thus, the whole structure can thus be represented as a sql net (Fig. S1, in ESI). Complex 2 crystallizes in a monoclinic system with C2/c space group. The asymmetric unit of 2 includes two crystallographically independent Zn2+ cations (Zn1 and Zn2), one ligand L, one IBG2− anion, and two water molecules, which were removed by the SQUEEZE routine in PLATON (Fig. 2a). Zn1 forms a tetrahedral structure coordinating with two N atoms and two O atoms, where two N atoms are from two independent L ligands and two O atoms are from two independent IBG2− anions. Zn2 has a similar coordination mode with Zn1 except that the bonding length and bonding angles are different. The bond lengths of
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Scheme 1. Synthetic scheme for the preparation of two complexes.
Zn1\\O and Zn1\\N are 1.950(4) Å and 1.972(4) Å. The bond angles of O\\Zn1\\O and N\\Zn1\\N are 105.2(2)° and 102.6(2)°, while the bond angle of O\\Zn1\\N is in the range 104.1(2)°–121.0(2)°. In comparison, the bond length of Zn2\\O is 1.973(4) Å and the bond length of Zn2\\N is in the range 2.016(8)–2.105(8) Å. The bond angles of O\\Zn2\\O and N\\Zn2\\N are 118.2(2)° and 81.2(5)°, while the bond angle of O\\Zn2\\N is in the range 99.4(3)°–128.0(3)°. Zn2+ cations are connected by IBG2− anions to form two linear chain structures as illustrated in red and blue color in Fig. 2b and c. These two linear chains are linked together by ligand L to from a 2-D planar structure with Zn2+ cation as the symmetric center. These planar structures are packed into layered super structure as shown in Fig. 2d. Due to the disorder of imidazole, the topology for complex 2 was analyzed by Diamond program. The Zn centers can be treated as 4-connected nodes, where L and IBG2− ligands are acting as linkers. Thus, the whole structure can thus be represented as a sql net (Fig. S2, in ESI). The abundant
hydrogen bonds in complexes 1 and 2 are presented in detail in Table S1 and Table S2 (in ESI), respectively. Due to hydrogen bond interactions, adjacent 2D layers of complexes 1 and 2 all are further packed into three-dimensional (3D) supramolecular frameworks. Powder X-ray diffraction analyses were carried out to confirm the purities of complexes 1 and 2, while the experimental data of both complexes are nearly consistent with their simulated data (Fig. S3 and S4, in ESI). It indicates that both complexes are successfully prepared as pure crystalline. Thermogravimetric analyses (TGA) were carried out in nitrogen atmosphere to examine the thermal stabilities of these complexes (Fig. 3). For complex 1, the weight loss of 7.12% in the range 20–280 °C is due to the loss of three lattice water molecules (calcd 7.20%), while after the temperature reaching 400 °C the complex 1 starts to decompose rapidly. For complex 2, the loss of two lattice water molecules before 200 °C gives a weight loss of 5.16% (calcd 5.41%). Then above 300 °C, the network of complex 2 starts to collapse
Fig. 1. (a) Coordination environment of the Zn(II) ions in complex 1. The hydrogen atoms and solvent molecules are omitted for clarity. Symmetry codes: #1 = x, −1 + y, z, #2 = 1 + x, y, z; (b) A view of the 2-D network; (c) The ABAB packing of two layered structures; (d) 3-D structure of complex 1 showing two types of mesopores A and B.
Y. Lou et al. / Inorganic Chemistry Communications 73 (2016) 183–186
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Fig. 2. (a) Coordination environment of the Zn(II) ions in complex 2. The hydrogen atoms and solvent molecules are omitted for clarity. Symmetry codes: # 1 = 2 − x, y, 2.5 − z, # 2 = 3 − x, y, 1.5 − z, # 3 = 1 + x, −y, 0.5 + z, # 4 = 2 − x, −y, 2 − z; (b) and (c) 2-D layers along c and b axes; (d) 2-D layered super structure of complex 2.
gradually. Complex 1 is more stable thermally than that of complex 2, which is probably due to the high stability of 3-D super structure based on ABAB packing of 2-D layers in complex 1. Luminescent microporous CPs constructed with d10 metal centers and conjugated organic linkers are promising candidates for applications as fluorescent sensors [11,27–29]. The solid-state luminescence properties of free ligand L, H2PPDA, H2IBG, complexes 1 and 2 are investigated at room temperature (Fig. 4). The fluorescent emission band of ligand L is occurred at 376 nm (λex = 286 nm), while H2PPDA shows emission band at 326 nm (λex = 280 nm) and H2IBG shows emission band at 446 nm (λex = 303 nm), respectively. These ligand emissions bands may be assigned to the π* → π or π* → n electronic transitions. Complex 1 shows two emission bands around 450 nm and 480 nm (λex = 286 nm) while complex 2 shows two emission bands around 445 nm and 480 nm (λex = 270 nm). Both complexes show same emission band around 480 nm, which is ascribed to the intra-ligand transition from ligand L. There is a red-shift of ~ 100 nm in comparison to
Fig. 3. TGA curves of complexes 1 and 2.
ligand L emission, which is due to the deprotonation and the stabilization of π* orbitals of ligand L by the electron withdrawing effect of the metal ion as commonly seen in d10 centered complexes [30–33]. The shoulder emission band around 486 nm in complex 1 is ascribed to the intraband transition of ligand PPDA2 −, where the red shift is due to the deprotonation and electron withdrawing effect of the metal ion [31–33]. The shoulder emission around 445 nm in complex 2 is ascribed to intra-ligand emission from IBG2−, where the deprotonation of H2IBG will not affect benzene π orbitals and there exists no direct interaction from metal ion with benzene π orbitals due to the spatial separation by methylene group. These two new complexes may be good candidates for novel hybrid inorganic-organic photoactive materials. In summary, two new amino-functionalized compounds were successfully prepared and characterized by the self-assembly of linear ligand L, V-shaped dicarboxylate ligands and Zn(II) salts under similar
Fig. 4. Solid-state photoluminescence spectra of L, H2PPDA, H2IBG, complexes 1 and 2 at room temperature and the excitation spectra of complexes 1 and 2.
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condition. These complexes exhibited interesting structural diversities due to the different flexibility of dicarboxylate ligands. The strong interaction between the ligand and metal ion is one of the important factors for the red-shift of ligand based emission seen in both complexes. Acknowledgements The authors would like to express thanks to Jiangsu Provincial Financial Support of Fundamental Conditions and Science and Technology for People's Livelihood for Jiangsu Key Laboratory of Advanced Metallic Materials (BM2007204), the National Natural Science Foundation of China (21475021, 21427807), the Natural Science Foundation of Jiangsu Province (BK20141331) and the Fundamental Research Funds for the Central Universities (2242016K40083). Appendix A. Supplementary material CCDC 1496053(1) and 1496054(2) contain the supplementary crystallographic data for this paper. Copies of the data can be obtained free of charge via bwww.ccdc.cam.ac.uk/conts/retrieving.htmlN, or from the Cambridge Crystallographic Data Centre, 12, Union Road, Cambridge, CB2 1EZ, U.K.; fax: +44 1223 336033; or email: [email protected]. uk. Detailed materials and physical measurements, additional powder X-ray diffraction spectra, topology drawings and single X-ray diffraction analyses are available as electronic supplementary information in the online version, at 10.1016/j.inoche.2016.10.028. References [1] Y. He, W. Zhou, G. Qian, B. Chen, Methane storage in metal-organic frameworks, Chem. Soc. Rev. 43 (2014) 5657–5678. [2] M.P. Suh, H.J. Park, T.K. Prasad, D.W. Lim, Hydrogen storage in metal-organic frameworks, Chem. Rev. 112 (2012) 782–835. [3] R.B. Getman, Y.S. Bae, C.E. Wilmer, R.Q. Snurr, Review and analysis of molecular simulations of methane, hydrogen, and acetylene storage in metal-organic frameworks, Chem. Rev. 112 (2012) 703–723. [4] H. Sato, W. Kosaka, R. Matsuda, A. Hori, Y. Hijikata, R.V. Belosludov, S. Sakaki, M. Takata, S. Kitagawa, Self-accelerating CO sorption in a soft nanoporous crystal, Science 343 (2014) 167–170. [5] S. Qiu, M. Xue, G. Zhu, Metal-organic framework membranes: from synthesis to separation application, Chem. Soc. Rev. 43 (2014) 6116–6140. [6] J.R. Li, J. Sculley, H.C. Zhou, Metal-organic frameworks for separations, Chem. Rev. 112 (2012) 869–932. [7] J. Liu, L. Chen, H. Cui, J. Zhang, L. Zhang, C.Y. Su, Applications of metal-organic frameworks in heterogeneous supramolecular catalysis, Chem. Soc. Rev. 43 (2014) 6011–6061. [8] M. Yoon, R. Srirambalaji, K. Kim, Homochiral metal-organic frameworks for asymmetric heterogeneous catalysis, Chem. Rev. 112 (2012) 1196–1231. [9] L.E. Kreno, K. Leong, O.K. Farha, M. Allendorf, R.P. Van Duyne, J.T. Hupp, Metal-organic framework materials as chemical sensors, Chem. Rev. 112 (2012) 1105–1125. [10] Z. Hu, B.J. Deibert, J. Li, Luminescent metal-organic frameworks for chemical sensing and explosive detection, Chem. Soc. Rev. 43 (2014) 5815–5840. [11] O.S. Wenger, Vapochromism in organometallic and coordination complexes: chemical sensors for volatile organic compounds, Chem. Rev. 113 (2013) 3686–3733. [12] W. Lu, Z. Wei, Z.Y. Gu, T.F. Liu, J. Park, J. Park, J. Tian, M. Zhang, Q. Zhang, T. Gentle 3rd, M. Bosch, H.C. Zhou, Tuning the structure and function of metal-organic frameworks via linker design, Chem. Soc. Rev. 43 (2014) 5561–5593.
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