Solvent and pH Driven Self-Assembly of Isomeric or Isomorphic

Jun 14, 2016 - However, complexes 1 and 3 share an unanticipated 2D layered structure while complex 2 presents an unprecedent topological network with...
1 downloads 10 Views 3MB Size
Subscriber access provided by UNIV OF NEBRASKA - LINCOLN

Article

Solvent and pH Driven Self-assembly of Isomeric or Isomorphic Complexes: Crystal Structure and Luminescent Change upon Desolvation Run-Ping Ye, Xin Zhang, Lei Zhang, Jian Zhang, and Yuan-Gen Yao Cryst. Growth Des., Just Accepted Manuscript • DOI: 10.1021/acs.cgd.6b00548 • Publication Date (Web): 14 Jun 2016 Downloaded from http://pubs.acs.org on June 15, 2016

Just Accepted “Just Accepted” manuscripts have been peer-reviewed and accepted for publication. They are posted online prior to technical editing, formatting for publication and author proofing. The American Chemical Society provides “Just Accepted” as a free service to the research community to expedite the dissemination of scientific material as soon as possible after acceptance. “Just Accepted” manuscripts appear in full in PDF format accompanied by an HTML abstract. “Just Accepted” manuscripts have been fully peer reviewed, but should not be considered the official version of record. They are accessible to all readers and citable by the Digital Object Identifier (DOI®). “Just Accepted” is an optional service offered to authors. Therefore, the “Just Accepted” Web site may not include all articles that will be published in the journal. After a manuscript is technically edited and formatted, it will be removed from the “Just Accepted” Web site and published as an ASAP article. Note that technical editing may introduce minor changes to the manuscript text and/or graphics which could affect content, and all legal disclaimers and ethical guidelines that apply to the journal pertain. ACS cannot be held responsible for errors or consequences arising from the use of information contained in these “Just Accepted” manuscripts.

Crystal Growth & Design is published by the American Chemical Society. 1155 Sixteenth Street N.W., Washington, DC 20036 Published by American Chemical Society. Copyright © American Chemical Society. However, no copyright claim is made to original U.S. Government works, or works produced by employees of any Commonwealth realm Crown government in the course of their duties.

Page 1 of 33

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Crystal Growth & Design

Solvent and pH Driven Self-assembly of Isomeric or Isomorphic Complexes: Crystal Structure and Luminescent Change upon Desolvation Run-Ping Ye, †,‡ Xin Zhang,† Lei Zhang,†Jian Zhang,† and Yuan-Gen Yao†,*



Key Laboratory of Coal to Ethylene Glycol and Its Related Technology, Fujian

Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian 350002, China. ‡

University of Chinese Academy of Sciences, 100049, Beijing, P. R. China

KEYWORDS: CPs; Solvent; Crystal structure; Fluorescence

*

To whom correspondence should be addressed. Dr. Yuan-Gen Yao Fax: +86-591-8371-4946; Tel: +86-591-6317-3138; E-mail: [email protected]

1 ACS Paragon Plus Environment

Crystal Growth & Design

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 2 of 33

ABSTRACT Three Cd(II) supramolecular isomers, namely, [Cd(IDPA)(H2O)]n·2n(H2O) (1), [Cd2(IDPA)2(H2O)3]n·n(DMF)·4n(H2O)

(2),

[Cd3(IDPA)3(DMA)(H2O)2n]·n(DMA)-

·n(H2O) (3) and two Cu(II) isomorphic complexes including [Cu(IDPA)(DMF)]n (4) and [Cu(IDPA)(H2O)]n

(5)

(DMF

=

N,N-dimethylformamide;

DMA

=

N,N-dimethylacetamide; H2IDPA =5-(1-oxoisoindolin-2-yl) isophthalic acid), have been synthesized under similar solvothermal conditions with different solvent systems and pH values. However, complexes 1 and 3 share an unanticipated 2D layered structure while complex 2 presents an unprecedent topological network with new point symbol of {4·62}{4·67·82}. Complexes 4 and 5 have been generated from [Cu2(COO)4] paddlewheels as the 4-connected node with the point symbol of {64·82}. The diverse structures of 1-5 can be much related with hydrogen bonds and π-π interactions. Furthermore, the luminescent properties of complexes 1–3 have been investigated before-and-after desolvation by heating at 220 °C for 2h. Interestingly, the quantum yield of complex 2 is changed from 37.20% to 10.73% after desolvation. These results indicate that solvent molecules actually enhance the photoluminescence instead of quenching it. The construction of these complexes shows that the solvent and pH value can regulate the crystal structure and luminescent properties.

2 ACS Paragon Plus Environment

Page 3 of 33

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Crystal Growth & Design

INTRODUCTION The design and self-assembly of coordination polymers (CPs) are of current interest not only due to their rich structural diversities but also owing to various potential applications in the fields of sensors, heterogeneous catalysis, gas storage, ion-exchange, and fluorescent materials.1-12 Recently, considerable progress in functional CPs has been achieved via thorough consideration of metal ions and free linkers with versatile geometry and multiple coordination sites.13,14 However, it is still impossible to accurately predict the crystal structure and properties because of many inscrutable factors, such as reaction temperature, solvent system, pH value of the reaction, secondary ligands and so on.6,15-18 On the basis of these factors, the rational design and synthesis of isostructural complexes and supramolecular isomers, which is the existence of two or more superstructures for given set of components, are more challenging topics.19-21 Meanwhile, the weak interactions including hydrogen bonds and π-π interactions are specific nonbonding interactions,22 which can serve as bridges to further extend the low-dimensional CPs to 3D supramolecular networks, increasing the complexity and robustness of the structure.23,24 Besides, these noncovalent interactions could not only enlarge the π-conjugate systems but also increase the efficiency of energy transfer from the ligand to ligand, leading to enhancing luminescent property.25 To the best of our knowledge, solvent plays an essential role in any solution reaction for the consideration of its solubility, polarity and steric effect.26,27 It has been indicated that the solvent coordinated with the metal centers or occupied the channel walls of crystal networks may result in diverse supramolecular isomers with unusual luminescent properties.20,28,29 For example, the reactions of H2BDC-Cl4 with Mn(OAc)2 in a variety of mixed solvents (H2O/pyridine, EtOH/MeOH, H2O/dioxane, and MeOH/DMF) result in four CPs with diverse dimensionality and connectivity.30 Herein, the coordination capability of solvent plays a significant role in directing the synthesis of supramolecular isomers.31,32 In our previous works, we have introduced a V-shaped semi-rigid multicarboxylate 3 ACS Paragon Plus Environment

Crystal Growth & Design

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 4 of 33

ligand (H4ODPT) to obtain five Zn(II)/ODPT complexes through solvothermal reactions under different pH conditions.33 Two isostructural complexes have been prepared under similar conditions only with different solvents.34 As a result, it is suggested that different complexes should be obtained by changing reaction conditions to reach the goal of target synthesis. In this work, a novel semi-rigid π-conjugated carboxylate ligand, 5-(1-oxoisoindolin-2-yl) isophthalic acid (H2IDPA), has been selected to react with Cd(II) or Cu(II) ions under similar solvothermal conditions with different solvent systems and pH values. It is noteworthy that the IDPA2- ligands with five oxygen atoms could form intramolecular hydrogen bonds C-H···O and intermolecular hydrogen bonds O-H···O with free water molecules, as well as π-π interactions among aromatic rings. Furthermore, few researches have been focused on guest-dependent photoluminescent property of Cd(II) CPs, which have the potential application in guest sensing and recognition.29,35 Considering all the above-mentioned aspects, we successfully developed three

novel

supramolecular

isomers,

namely,

[Cd2(IDPA)2(H2O)3]n·n(DMF)·4n(H2O) (H2O)2n]·n(DMA)·n(H2O)

(3)

[Cu(IDPA)(DMF)]n (4) and

and

[Cd(IDPA)(H2O)]n·2n(H2O) (1),

(2), two

isomorphic

[Cd3(IDPA)3(DMA) complexes

including

[Cu(IDPA)(H2O)]n (5) (DMF = N,N-dimethylformamide;

DMA = N,N-dimethylacetamide). The structures and thermal performances of 1–5 were systematically characterized. In addition, guest-dependent luminescent properties of 1-3 have also been discussed in detail.

EXPERIMENTAL SECTION Materials and measurements All materials and solvents for synthesis were purchased and used without further purification. Elemental analyses of C, H and N were carried on an EA1110 CHNS-0 CE elemental analyzer. FT-IR spectra were recorded with KBr pellets on a Nicolet Magna 750 FT-IR spectrometer in the 4000-400 cm-1 region (Figure S1, Supporting Information). Powder X-ray diffraction (PXRD) analyses were performed on a Rigaku 4 ACS Paragon Plus Environment

Page 5 of 33

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Crystal Growth & Design

Dmax2500 diffractometer with Cu-Kα radiation (λ= 1.54056 Å). Thermogravimetric spectrometric analysis (TGA) data were collected at a heating rate of 10 K·min-1 on a NETSCHZ STA-449C thermal analyzer from 30 to 990 °C under N2 atmosphere. The solid-state luminescence spectra were measured at ambient temperature using a HITACHI F-4600 luminescence spectrophotometer. The quantum yields (QY) were recorded by a FLS920 Edinburgh Spectrophotometer in the solid-state at 298 K.

Syntheses of complexes [Cd(IDPA)(H2O)]n·2n(H2O) (1) In a 20 mL capped vial, Cd(NO3)2·4H2O (0.0246 g, 0.1 mmol) and H2IDPA (0.0297 g, 0.1 mmol) were dissolved in 2 mL H2O and 1 mL DMF. The pH value was adjusted to 9.5 using 0.5 mol/L NaHCO3 solution, then the final mixture was heated at 90 °C for 2 d. After naturally cooling to ambient temperature, colorless block-crystals of 1 were obtained in the yield of 0.0235 g, 51 % (based on H2IDPA ligand). Anal. calcd for C16H15CdNO8 (461.70): C 41.59, H 3.25, N 3.03 %. Found: C 41.65, H 3.37, N 3.12 %. IR/cm-1 (KBr): 3611 (w), 3215 (w), 1664 (m), 1569 (s), 1372 (s), 1101 (m), 909 (w), 783 (m), 731 (m).

[Cd2(IDPA)2(H2O)3]n·n(DMF)·4n(H2O) (2) The same prepared procedure as that for 1was employed for 2 except that using 0.5 mol/L NaOH solution instead of 0.5 mol/L NaHCO3 solution to tune the pH value to 11. Colorless block-crystals of 2 were obtained with the yield of 0.0243 g, 48 % (based on H2IDPA ligand). Anal. calcd for C35H39Cd2N3O18 (1014.51): C 41.40, H 3.84, N 4.14 %. Found: C 41.56, H 3.91, N 4.09 %. IR/cm-1 (KBr): 3605 (m), 3085 (w), 1679 (m), 1559 (s), 1377 (s), 1086 (m), 940 (w), 783 (m), 731 (m).

[Cd3(IDPA)3(DMA)(H2O)2n]·n(DMA)·n(H2O) (3) The preparation of 3 was carried out in a procedure similar to that for 2 except that using DMA (1 mL) instead of DMF (1 mL). Colorless block-crystals of 3 were obtained with 5 ACS Paragon Plus Environment

Crystal Growth & Design

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 6 of 33

the yield of 0.0314g, 65% (based on H2IDPA ligand). Anal. calcd for C56H51Cd3N5O20 (1451.25): C 46.30, H 3.51, N 4.82 %. Found: C 46.41, H 3.47, N 4.88 %. IR/cm-1 (KBr): 3605 (m), 3215 (w), 1637 (s), 1569 (s), 1367 (s), 1086 (m), 929 (w), 778 (m), 731(m).

[Cu(IDPA)(DMF)]n (4) In a 20 mL capped vial, Cu(CH3COO)2·H2O (0.0204 g, 0.1 mmol) and H2IDPA (0.0297 g, 0.1 mmol) were dissolved in 2 mL DMF and 1 mL H2O. The pH value was adjusted to 5.5 using concentrated HNO3 solution, then the final mixture was heated at 90 °C for 2 d. After naturally cooling to ambient temperature, blue piece-shaped crystals were collected with the yield of 0.0233 g, 54 % (based on H2IDPA ligand). Anal. calcd for C19H16CuN2O6 (431.89): C 52.79, H 3.70, N 6.48 %. Found: C 53.01, H 3.65, N 6.55 %. IR/cm-1 (KBr): 3697 (m), 1703 (m), 1626 (m), 1582 (m), 1371 (s), 1080 (m), 925 (m), 783 (m), 731 (m).

[Cu(IDPA)(H2O)]n (5) The preparation of 5 was carried out in a procedure similar to that for 4 except that using DEF (2 mL, DEF= N,N-diethylformamide) instead of DMF (2 mL). Blue piece-shaped crystals were collected with the yield of 0.0256 g, 68 % (based on H2IDPA ligand). Anal. calcd for C16H11CuNO6 (376.81): C 50.95, H 2.92, N 3.72 %. Found: C 50.89, H 2.85, N 3.65 %.

IR/cm-1 (KBr): 3742 (w), 3388 (s), 1696 (s), 1632 (s), 1588 (s), 1371

(s), 1109 (w), 904 (m), 776 (m), 731 (m).

Single-crystal X-ray diffraction determination Crystal data for complexes 1-5 were collected on an Oxford Xcalibur E diffractometer with a graphite monochromatic Mo-Kα radiation (λMo-Kα = 0.71073 Å) at 298K. Empirical absorption corrections were applied using the SADABS program.36 The structures were solved by the direct method (SHELXS-97) and refined by full-matrix least-squares (SHELXL-97) on F2.37 The non-hydrogen atoms were refined by anisotropic thermal parameters and hydrogen atoms were fixed geometrically and 6 ACS Paragon Plus Environment

Page 7 of 33

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Crystal Growth & Design

refined by using a riding model. The crystal data and structural refinements of 1–5 are summarized in Table 1. Selected bond lengths and bond angles are listed in Table S1 of the Supporting Information. CCDC numbers of 1417807, 1417806, 1417808, 1417804 and 1470904 are for 1–5, respectively.

Table 1. Crystallographic data and structure refinements for complexes 1-5. Complex

1

2

3

4

Empirical formula

C16H15CdNO8

C35H39Cd2N3O18

C56H51Cd3N5O20

C19H16CuN2O6

C16H11CuNO6

Crystal color

Colorless

Colorless

Colorless

Blue

Blue

Formula weight

461.70

1014.51

1451.25

431.89

376.81

Crystal system

Orthorhombic

Monoclinic

Orthorhombic

Trigonal

Trigonal

Space group

Pbca

P21/c

Pna21

R-3

R-3

a (Å)

6.8811(3)

15.3115(4)

20.3302(5)

21.8544(6)

21.2498(2)

b (Å)

17.9151(6)

13.4202(4)

10.7455(3)

21.8544(6)

21.2498(2)

c (Å)

25.7736(8)

19.1497(5)

24.2964(6)

21.3069(9)

22.0147(3)

α (°)

90.00

90.00

90.00

90.00

90.00

β (°)

90.00

99.467(2)

90.00

90.00

90.00

90.00

90.00

90.00

120.00

120.00

3177.3(2)

3881.35(18)

5307.7(2)

8813.1(5)

8609.00(16)

8

4

4

18

18

Dcalcd (g·cm )

1.930

1.736

1.816

1.465

1.308

-1

µ (mm )

1.423

1.178

1.278

1.152

1.863

F(000)

1840.0

2040.0

2904.0

3978.0

3438.0

Rint [I > 2θ]

0.0371

0.0700

0.0281

0.0652

0.0828

Rw2 [I > 2θ]

γ (°) 3

V (Å ) Z -1

5

0.0747

0.2081

0.0582

0.1993

0.2735

a

0.0747

0.0889

0.0330

0.0779

0.0874

b

Rw2 all

0.0817

0.2242

0.0601

0.2106

0.2801

S

1.096

1.044

1.051

1.089

1.107

Rint all

a

Rint =Σ||Fo| − |Fc||/Σ|Fo|.

b

Rw2=[Σw(Fo2



Fc2)2/Σw(Fo2)2]1/2

RESULTS AND DISCUSSION Preparation of the complexes 1-5 As a derivative of benzene-1,3-dicarboxylic acid, H2IDPA contains five potential 7 ACS Paragon Plus Environment

Crystal Growth & Design

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 8 of 33

coordination sites that can bridge metal ions into novel and diversified structures and topologies via its multiple bridging modes. In this paper, complexes 1–5 were obtained via the solvothermal reactions of multicarboxylate ligand and metal salt with the molar ratio of 1:1 (Scheme 1). The reaction temperature was held at 90 °C for 48 h and then cooled to ambient temperature, obtaining good single crystals of five CPs with high yield. Actually, complexes 1–5 can only be obtained at relatively low temperatures below 120 °C, and higher than this temperature only gave amorphous powders. As H2IDPA could well dissolve in solvents of DMF, DMA and DEF, complexes 2 and 3 are synthesized using the same reaction mixtures in different solvents as well as complexes 4 and 5. In addition, complexes 1 and 2 were obtained in the same solvents through regulation of the pH value. Notably, complexes 1–5 are stable in the solid-state when exposed to air, especially that 1-3 can keep their crystalline states even upon removal the guest molecules at 220 °C.

Scheme 1. Synthetic procedures of complexes 1-5. 8 ACS Paragon Plus Environment

Page 9 of 33

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Crystal Growth & Design

Structural description for complexes 1–5 Structure of [Cd(IDPA)(H2O)]n·2n(H2O)

(1). Single crystal X-ray structural study

reveals that complex 1 crystallizes in the orthorhombic space group Pbca and features a 2D layered structure. As shown in Figure 1a, the asymmetric unit of 1 has one independent Cd(II) ion, one IDPA2- ligand, one terminal H2O ligand and two lattice H2O molecules. The Cd(II) ion is located in a distorted octahedral coordination environment completed by five carboxylate O atoms from IDPA2- ligands and one terminal H2O ligand. In addition, the lengths of Cd–O bond range from 2.179(3) to 2.509(3) Å, which are greatly matched with previous reports about Cd(II)-carboxylates.38,39 As shown in Table S2 and Figure 1d, the distances of intermolecular π-π interactions among aromatic rings of IDPA2- ligands are 3.546(3) Å and 3.692(3) Å, which are in agreement with previous studies.40,41 Because of the presence of a large number of water molecules, numerous hydrogen bond donors (O atoms from H2O or C atoms from IDPA2-) and acceptors (O atoms from IDPA2- and H2O) to construct a hydrogen bond networks including intermolecular hydrogen bonds O-H···O and intramolecular hydrogen bonds C-H···O. Therefore, the interlayers of 1 further connect into a 3D supramolecular network via the synergetic interactions of hydrogen bonding and π-π interactions (Table S3 and Figure 1c). To the best of our knowledge, it remains rare that a complicated supramolecular architecture is assembled from the simple layers via both hydrogen bonding interactions and π-π interactions. Here, the carboxylate groups of IDPA2-

ligand

display

two

different

modes:

µ2-η1:η1-bridging

mode

and

µ2-η2:η1-bridging mode (Scheme 2a). Furthermore, the 2D layered structure could be simplified into a classical sql topological network with the point symbol of {44·62} when the Cd1 ions and IDPA2- ligands were looked as 4-connected nodes (Figure 1b, Figure S2, Supporting Information).

9 ACS Paragon Plus Environment

Crystal Growth & Design

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 10 of 33

Scheme 2. Coordination modes of the H2IDPA ligands in complexes 1–5. [(a) for 1-3, (b) for 2, (c-d) for 3, (e) for 4-5]

Figure 1. (a) Coordination geometry of metal ion in 1. (b) The 2D layer of 1 in plane bc. (c) 3D supramolecular network of 1 via hydrogen bonds and π-π interactions (d). [Symmetry codes: (i) x+1/2, y, -z+3/2 for O2A; (ii) -x+1, y+1/2, -z+3/2 for O3B and O4B; (iii) -x+3/2, y+1/2, z for O4C].

10 ACS Paragon Plus Environment

Page 11 of 33

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Crystal Growth & Design

Structure of [Cd2(IDPA)2(H2O)3]n·n(DMF)·4n(H2O)

(2). By using 0.5 mol/L NaOH

solution instead of 0.5 mol/L NaHCO3 solution to tune the pH value to 11, complex 2 was obtained. It features an unusual 3D frameworks crystallized in the monoclinic space group P21/c (Figure 2d). As depicted in Figure 2a, the asymmetric unit of 2 contains two independent Cd(II) ions, two IDPA2- ligands, three coordinated H2O molecules, one free DMF molecule and four free H2O molecules. Both Cd1 and Cd2 are seven-coordinated with distorted monocapped octahedral geometries. For Cd1, it was coordinated by four carboxylate O atoms from four independent IDPA2- ligands and three coordinated H2O molecules. While for Cd2, it was coordinated by seven carboxylate O atoms from four independent IDPA2-. The Cd–O (Cd1–O and Cd2–O) bond lengths are in the range of 2.227(6)–2.605(7) Å, which are well matched with previous reports.42-44 It is noteworthy that there are eight guest molecules in a fundamental unit of 2, thus numerous of intramolecular and intermolecular hydrogen bonds are obviously observed in 2. In addition, the distances of intermolecular π-π interactions are 3.451(5) Å and 3.449(5) Å, which further sustain the grid network of 2 with the synactic effect of hydrogen bonds (Figure 2e, Table S2 and Figure S3, Supporting Information). As shown in Scheme 2a and b, four carboxylate groups of two independent IDPA2ligands adopt three different coordination modes: µ2-η1:η1-bridging mode, η2-chelating mode and µ2-η2:η1-bridging mode. Besides, it is worth noting that the oxygen atom (O5A) from the isoindolin-1-one (idl) group of IDPA2- ligand has been coordinated to Cd1. It is because of such coordination modes that the two Cd(II) ions are integrated together by four COO- groups, forming a binuclear building unit [Cd2(COO)4] with the nonbonding Cd1⋯Cd2 separation of 3.6405(10) Å (Figure 2b). In the framework of 2, one independent IDPA2- ligand (denoted as A-type) links three dinuclear [Cd2(COO)4] units, another independent IDPA2- ligand (denoted as B-type) links two dinuclear [Cd2(COO)4] units and each dinuclear [Cd2(COO)4] unit links three type-A IDPA2- ligands and two dinuclear [Cd2(COO)4] units via two type-B IDPA2- ligands. As described above, we can define type-A IDPA2- ligands, dinuclear [Cd2(COO)4] units and type-B ligands as 3-, 5-connected nodes, linear linkers, respectively (Figure 2c). Through this simplification, 11 ACS Paragon Plus Environment

Crystal Growth & Design

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 12 of 33

the complicated framework of 2 can be reduced into a binodal (3,5)-connected topological network with the point symbol of {4·62}{4·67·82} (Figure 2f).To our best knowledge, although some CPs with bimodal (3,5)-connected topologies have been reported before, complex 2 reported here is an unprecedent topological network with new topological symbol.45,46

Figure 2. (a) Coordination geometries of metal ions in 2. (b) Binuclear [Cd2(COO)4] building unit. (c) Schematic representations of the 3- and 5-connected nodes. (d) The 3D polyhedra network of 2. (e) π-π interactions in 2. (f) The (3,5)-connected topology of 2. [Symmetry codes: (i) -x+1, -y+1, -z+1 for O5A; (ii) -x, y+1/2, -z+1/2 for O8B and O9B; (iii) -x+1, y-1/2, -z+1/2 for O3C and O4C].

Structure of [Cd3(IDPA)3(DMA)(H2O)2n]·n(DMA)·n(H2O) (3). Complex 3 was obtained by using DMA (1mL) instead of DMF (1mL), and the single crystal X-ray diffraction analysis reveals that the asymmetric unit of complex 3 consists of three crystallographically independent Cd(II) ions, three independent IDPA2- ligands, two 12 ACS Paragon Plus Environment

Page 13 of 33

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Crystal Growth & Design

DMA molecules and three H2O molecules. As shown in Figure 3a, both Cd2 and Cd3 are six-coordinated with distorted octahedral geometries surrounded by six carboxylate O atoms from five IDPA2- ligands for Cd2, three carboxylate O atoms from two IDPA2ligands, one DMA molecule and two coordinated H2O molecules for Cd3, respectively. Unlike Cd2 and Cd3, Cd1 is ligated to seven oxygen atoms from five different IDPA2ligands. As shown in Figure 3b, three independent Cd(II) ions are connected by six COO- group, thus generating a trinuclear [Cd3(COO)6] building unit with the average nonbonding Cd···Cd separation is of 4.8864(6) Å. The Cd–O bond distances vary from 2.218(3) to 2.528(4) Å, which are in the normal range according to previously reported cadmium carboxylate complexes.34 As shown in Figure 3c-d, it shows that the voids (1480.4 Å3) in complex 3 occupy 27.9% of the crystal volume (5307.8 Å3) after removal of the guest molecules by calculations using PLATON.47 Obviously, the O-H···O and C-H···O hydrogen bonds as well as π-π interactions also play a critical role in the formation of 3D supramolecular frameworks of 3. It can be found that the short distances of adjacent aromatic rings are 3.462(3), 3.799(3), and 3.964(3) Å and the lengths of D⋯A are in the range of 2.710(6)-2.974(6) Å (Figure S4 and Table S2-S3, Supporting Information). Compared to 2, there are three coordination modes of the carboxylate groups in 3: µ2-η1:η1-bridging mode, η2-chelating mode and µ2-η2:η1-bridging mode (Scheme 2a, c and d). Similar to that in 2, some oxygen atoms from the idl group of IDPA2- ligands have also coordinated to Cd(II) ions. It is easy to understand the topological network of 3 by choosing the trinuclear [Cd3(COO)6] building unit as a node. As shown in Figure 3e, one independent node links four others, resulting in a 4-connected sql topology with the point symbol of {44·62}.

13 ACS Paragon Plus Environment

Crystal Growth & Design

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 14 of 33

Figure 3. (a) Coordination geometries of metal ions in 3. (b) Trinuclear [Cd3(COO)6] building unit. (c) The 2D polyhedra layer of 3. (d) Space-filling model of complex 3 on the ab plane. (e) The 4-connected topology of 3. [Symmetry codes: (i) x, y+1, z for O8A and O9A; (ii) x+1/2, -y+1/2, z for O3B, O4B, O13B and O14B].

Structure of [Cu(IDPA)(DMF)]n (4) and [Cu(IDPA)(H2O)]n (5) X-ray crystal structure analysis shows that complexes 4 and 5 belong to a trigonal system with space group R-3 and feature 3D frameworks with narrow channels parallel to the c axis. Because complexes 4 and 5 are isostructural, complex 4 was chosen as a representative to depict the crystal structure in detail. There are one Cu (II) ion, one IDPA2- ligand and one coordinated DMF molecule in the fundamental unit. As shown in Figure 4a, Cu1 exhibits tetragonal pyramid geometry: four O atoms (O1, O2A, O3B, O4C) from four separate IDPA2- ligands and one O atom (O6) from DMF molecule. The lengths of Cu–O bonds span the range of 1.954(4) to 2.150(5) Å and the angles of O– Cu–O angle amount from 90.28(19) to 169.02(19) ° (Table S1, Supporting Information). It is worth noting that the four atoms (O1, O1C, O2, O2C) lie in a plane and another four atoms (O3, O3A, O4, O4A) also lie in another plane, which rotate angles of 21° and 9° 14 ACS Paragon Plus Environment

Page 15 of 33

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Crystal Growth & Design

from the plane of the benzene ring, respectively (Figure 4b). As shown in Figure 4c-d, a large number of apertures in this structure are occupied by the idl group and solvent molecules. As a result, removal of DMF molecules would afford considerable free volume of 3406.4 Å3 per unit cell, which is calculated to be 38.7 % of the volume of the unit cell (PLATON).47 It is noteworthy that large numbers of π-π stacking interactions and intramolecular C-H⋯O hydrogen bonds also exist in 4 to stabilize its framework (Figure 4e, Table S2-S3, Supporting Information). The coordination modes of IDPA2- ligands in 4 and 5 are shown in Scheme 2e, suggesting that the carboxylate groups adopt only one coordination mode: µ2-η1:η1-bridging mode. Two adjacent Cu(II) ions are integrated together by occupying four carboxyl groups, forming a paddlewheel shaped [Cu2(COO)4] building subunit as a 4-connected node (Figure 4e). Furthermore, the intricate frameworks of 4 and 5 can be simplified into a unique single-node nbo topology with the point symbol of {64·82} (Figure 4f). It is an undeniable fact that this is a desirable example of nbo topology because its 3D structure is open and noninterpenetrating.48,49

15 ACS Paragon Plus Environment

Crystal Growth & Design

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 16 of 33

Figure 4. (a) Coordination geometry of metal ion in 4. (b) Plane angles between carboxy groups and benzene ring: green, plane of O1···O1C···O2···O2C; grey, plane of O3···O3A···O4···O4A; yellow, plane of the benzene ring in IDPA2-. (c) 3D structure of 4. For clarity, the idl group and coordinated DMF are omitted. (d) Packing structure of 4. (e) Binuclear [Cu2(COO)4] building unit, hydrogen bonds and π-π interactions in 4. (f) The 4-connected nbo topology of 4. [Symmetry codes: (i) x-y+1/3, x-1/3, -z+5/3 for O2A; (ii) -x+y+2/3, -x+1/3, z+1/3 for (O3B); (iii) -x+1, -y, -z+2 for O4C].

Effects of solvent system and pH value on assembly of supramolecular network Both complexes 1 and 2 were prepared through similar conditions except that the only difference was the pH value of the reaction, resulting in different structures between them. Complex 1 presents a 2D layered structure and forms 3D supramolecular network via weak non-bonding interactions while complex 2 is a 3D frameworks with a unique (3,5)-connected {4·62}{4·67·82} topology, which is probably because that the pH value influence the coordination environments of the ligands. In a comparison of coordination modes of H2IDPA in 1-3, the oxygen atom of idl group was only coordinated metal ions at a relatively high pH value. Furthermore, the solvents are DMF/H2O (3 mL, 1/2) and DMA/H2O (3 mL, 1/2) for 2 and 3, respectively. The crystal structures and topologies of 2 and 3 are different, which can be assigned to solvents act as the component (both ligand and guest) merged into the complex to influence the final architecture. However, the solvents for 4 and 5 are also not consistent while the structures of them are isostructural. We can draw a conclusion that solvents and pH value play significant roles in the supramolecular isomerism and isomorphism.34

Thermal properties and Powder X-ray diffraction The thermal experiments for complexes 1-5 were performed to study their thermal stabilities (Figure S5a-b, Supporting Information). The TGA curve of 1 shows that the free and coordinated H2O molecules are lost from 30 to 174 °C (obsd: 11.03%, calcd: 11.69%). The decomposition of the residual component is observed at 359 °C. According 16 ACS Paragon Plus Environment

Page 17 of 33

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Crystal Growth & Design

to the TGA curve of 2, the first weight loss of 6.93% (calcd: 7.10%) observed below 123 °C can be considered to the departure of uncoordinated H2O molecules. Then the free DMF molecules go on losing from 123 to 156 °C (obsd: 7.59%, calcd: 7.19%). For 3, the weight loss of 7.78% (calcd: 7.23%) in the range of 54-152 °C is corresponding to the removal of free H2O and DMA molecules. After 152 °C, the anhydrous compound begins to sharply collapse probably owing to the loss of the coordinated guest molecules and decomposition of the organic components. Interestingly, complexes 4 and 5 display the similar thermal stabilities due to their isomorphic structure (Figure S5b, Supporting Information). The weight loss from 60 to 189 °C can be attributed to the removal of all the guest molecules. (obsd: 16.10% for 4 and 4.97% for 5; calcd: 16.90% for 4 and 4.78% for 5). After heating beyond 370 °C, the coordinated ligands occur to collapse, resulting in an unidentified framework. To examine the purities and homogeneities of 1-5, we synthesized the five products and characterized them through PXRD at 298 K. It was confirmed that the peak positions of the measured patterns were well consistent with the simulated peaks (Figure S6–S7, Supporting Information). Besides, it was worth noting that 1-3 had excellent thermal stabilities before 300 °C besides losing guest molecules. When treating 1-3 at 220 °C for 2h, the PXRD patterns of the desolvated samples were still well matched with the simulated ones (Figure S6, Supporting Information). This phenomenon indicated that 1-3 can keep stable even upon the removal of guest molecules.50

Photoluminescence properties The solid-state luminescence behaviors of 1–3 and H2IDPA have been investigated at 298 K with the excitation wavelength upon 340 nm for complexes 1-3. As shown in Figure 5a, the emission of H2IDPA centered at 441 nm upon 365 nm excitation, which can be probably attributed to π*→ n and π* → π of intraligand nature.51 Despite the fact that different structural frameworks among complexes 1–3, their solid-state emission bands are close to each other as depicted in Figure 5a and table 2, which may be derived from intraligand and ligand-to-ligand charge transition. Compared to the free 17 ACS Paragon Plus Environment

Crystal Growth & Design

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 18 of 33

H2IDPA, the emission maximum of all complexes exhibit a large blue shift (16, 29, 14 nm for 1-3, respectively), which is probably due to the effect of the linker coordination to metal ions.52,53 In addition, research on fluorescence quantum yield (QY) of free ligands and 1-3 were carried on and listed in Table 2. Notably, the enhanced QY of 1-3 (QYH2IDPA=4.41%, QY1=35.52, QY2=37.20 and QY3=31.83 ) primarily stems from longer intermolecular separations, the hydrogen bonds and π-π interactions, and the increased rigidity of fluorescent linkers as well as extended π-conjugated system.54 Comparing the coordination modes of the H2IDPA ligand, it is interesting that the linker employs four different connection types in 1-3 and the oxygen atom from the idl group of IDPA2- ligand has coordinated to metal ions only in 2 and 3. As a consequence, 2 possesses a 3D rigid network with much weak non-bonding interactions, whereas 1 and 3 have lower dimensional layers. Therefore, the luminescent property of 2 is better than that in 1 and 3.

Figure 5. The emission spectra of H2IDPA and 1–3 before-and-after desolvation in the solid-state at 298 K. (a-Before, b-After, the insert pictures were shown under the illumination of the UV lamp, λex=365 nm)

18 ACS Paragon Plus Environment

Page 19 of 33

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Crystal Growth & Design

Table 2. The photoluminescence data of the free linker and complexes 1-3 before-and-after desolvation.

Sample

Excitation wavelength (nm)

Emission Wavelength (nm)

Quantum yield (%)

H2IDPA

365

441

4.41

1

340

425

35.52

2

340

412

37.20

3

340

427

31.83

H2IDPA’

340

427, 451

6.57

1’

350

425, 448

11.26

2’

350

422, 448

10.73

3’

350

407, 450

11.69

In order to further study the influence of solvent on photoluminescence properties, 1-3 were heated at 220 °C for 2 h in solid-state. After a slow cooling to room temperature, complexes 1’-3’ were obtained upon desolvation. As shown in Figure 5b, the desolvated complexes 1’-3’ show luminescence with intensity only half or less than that of complexes 1-3. Furthermore, the QY of 2 is changed from 37.20% to 10.73% after desolvation in the solid-state (Figure 6 for 2 and 2’, Figure S8-S10 for H2IDPA and H2IDPA’, 1 and 1’, 3 and 3’ respectively, Supporting Information), which is presumably due to the multiple π-π interactions and hydrogen bonds in the packing structure of 2 rigidifying the IDPA2- ligands and decreasing the thermal motion of aromatic rings.55 When the free and coordinated solvent molecules of the complexes were desolvated, the hydrogen bonds were destroyed and the environment of Cd(II) ion become soft. This is likely suggest that the desolvated frameworks exist lots of defects or hanging bonds around metal ions, resulting in drastically increasing the radiationless process.29 All these studies provide wider ground for choice and application of these complexes in the field of guest-dependent luminescent materials.

19 ACS Paragon Plus Environment

Crystal Growth & Design

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 20 of 33

Figure 6. The QY curves of complex 2 before-and-after desolvation (a-Before-2, b-After-2’).

CONCLUSIONS We have successfully obtained three Cd(II) supramolecular isomers and two Cu(II) isomorphic complexes based on a bulky dicarboxylate ligand (H2IDPA). The diverse structures of 1-5 illustrate that the construction of attractive supramolecular architectures can be much related to hydrogen bonds and π-π interactions. Interestingly, complex 2 not only features a 3D frameworks with a new binodal (3,5)-connected {4·62}{4·67·82} topology, but also exhibits a high QY of 37.20% compared with free links (QY= 4.41%). However, the luminescent intensity and QY of the complexes 1-3 have dramatically decreased after desolvation, which is probably because that the environment around Cd(II) ion was softened in the amorphous desolvated phases. These results reveal that solvents act a pivotal part in the construction of 1–3 as well as their luminescent properties. In conclusion, the solvent and pH induced supramolecular isomers 1–3 may be used as potential guest-dependent luminescent materials.

20 ACS Paragon Plus Environment

Page 21 of 33

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Crystal Growth & Design

ASSOCIATED CONTENT Supporting Information Additional tables, IR, TGA, PXRD, CIF files, as well as the QY curves of free ligands, complexes 1 and 3. This information is available free of charge via the Internet at http://pubs.acs.org.

AUTHOR INFORMATION Corresponding Author *Corresponding Author e-mail: [email protected]

ACKNOWLEDGMENT This work was supported by the “Strategic Priority Research Program” of the Chinese Academy of Sciences (XDA07070200, XDA09030102), the Science Foundation of Fujian Province (2006l2005) and Fujian industrial guide project (2015H0053).

REFERENCES (1) Comotti, A.; Bracco, S.; Sozzani, P.; Horike, S.; Matsuda, R.; Chen, J.; Takata, M.; Kubota, Y.; Kitagawa, S. J. Am. Chem. Soc. 2008, 130, 13664–13672. (2) Wang, X. L.; Qin, C.; Wang, E. B.; Lia, Y. G.; Su, Z. M. Chem. Commun. 2005, 43, 5450–5452. (3) Liu, L.; Han, Z. B.; Wang, S. M.; Yuan, D. Q.; Ng, S. W. Inorg. Chem. 2015, 54, 3719–3721. (4) Kreno, L. E.; Leong, K.; Farha, O. K.; Allendorf, M.; Duyne, R. P. V.; Hupp, J. T. Chem. Rev. 2012, 112, 1105–1125. (5) Li, B. Y.; Zhang, Y. M.; Ma, D. X.; Li, L.; Li, G. H.; Li, G. D.; Shi, Z.; Feng , S. H. Chem. Commun. 2012, 48, 6151–6153. (6) Gándara, F.; Gomez-Lor, B.; Gutiérrez-Puebla, E.; Iglesias, M.; Monge , M. A.; Proserpio, D. M.; Snejko, N. Chem. Mater. 2008, 20, 72–76. (7) Sumida, K.; Rogow, D. L.; Mason, J. A.; McDonald, T. M.; Bloch, E. D.; Herm, Z. R.; Bae , T.-H.; Long, J. R. Chem. Rev. 2012, 112, 724–781. 21 ACS Paragon Plus Environment

Crystal Growth & Design

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 22 of 33

(8) Sun, L. B.; Li, A. G.; Liu, X. D.; Liu, X. Q.; Feng, D. W.; Lu, W. G.; Yuan, D. Q.; Zhou, H. C. J. Mater. Chem. A 2015, 3, 3252–3256. (9) Tan, Y. X.; He, Y. P.; Zhang, J. Chem. Commun. 2014, 50, 6153–6156. (10) Ye, R. P.; Zhang, X.; Zhai, J. Q.; Qin, Y. Y.; Zhang, L.; Yao, Y. G.; Zhang, J. CrystEngComm 2015, 17, 9155–9166. (11) Wei, Z.; Gu, Z. Y.; Arvapally, R. K.; Chen, Y. P.; McDougald, R. N., Jr.; Ivy, J. F.; Yakovenko, A. A.; Feng, D.; Omary, M. A.; Zhou, H. C. J. Am. Chem. Soc. 2014, 136, 8269–8276. (12) Yang, W.; Wang, C. M.; Ma, Q.; Feng, X. N.; Wang, H. L.; Jiang, J. Z. Cryst. Growth Des. 2013, 13, 4695–4704. (13) Kitagawa, S.; Matsuda, R. Coord. Chem. Rev. 2007, 251, 2490–2509. (14) Tanaka, D.; Masaoka , S.; Horike1, S.; Furukawa, S.; Mizuno , M.; Endo, K.; Kitagawa, S. Angew. Chem. Int. Edit. 2006, 118, 4744–4747. (15) Zhang , X.; Huang, Y. Y.; Cheng, J. K.; Yao , Y. G.; Zhang, J.; Wang, F. CrystEngComm 2012, 14, 4843–4849. (16) Cheng, J. K.; Yao, Y. G.; Zhang, J.; Li, Z. J.; Cai, Z. W.; Zhang, X. Y.; Chen, Z. N.; Chen, Y. B.; Kang, Y.; Qin, Y. Y.; Wen, Y. H. J. Am. Chem. Soc. 2004, 126, 7796–7797. (17) Oh, M.; Stern, C. L.; Mirkin, C. A. Inorg. Chem. 2005, 44, 2647–2653. (18) Chen , X. L.; Zhang, B.; Hu, H. M.; Fu, F.; Wu, X. L.; Qin, T.; Yang , M. L.; Xue, G. L.; Wang, J. W. Cryst. Growth Des. 2008, 8, 3706–3712. (19) Zhu, X.; Liu, X. G.; Li, B. L.; Zhang, Y. CrystEngComm 2009, 11, 997–1000. (20) Gong, Y.; Liu, J.; Hu, C.; Gao, W. Inorg. Chem. Commun. 2007, 10, 575–579. (21) Masaoka, S.; Tanaka, D.; Nakanishi, Y.; Kitagawa, S. Angew. Chem. 2004, 116, 2584–2588. (22) Peresypkina, E.; Virovets, A.; Scheer, M. Cryst. Growth Des. 2016, 16, 2335–2341. (23) Du, X.; Fan, R.; Wang, X.; Qiang, L.; Wang, P.; Gao, S.; Zhang, H.; Yang, Y.; Wang, Y. Cryst. Growth Des. 2015, 15, 2402–2412. (24) Bhattacharya, S.; Goswami, A.; Gole, B.; Ganguly, S.; Bala, S.; Sengupta, S.; Khanra, S.; Mondal, R. Cryst. Growth Des. 2014, 14, 2853–2865. (25) Mikhalyova, E. A.; Yakovenko, A. V.; Zeller, M.; Kiskin, M. A.; Kolomzarov, Y. V.; Eremenko, I. L.; Addison, A. W.; Pavlishchuk, V. V. Inorg. Chem. 2015, 54, 3125–3133. 22 ACS Paragon Plus Environment

Page 23 of 33

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Crystal Growth & Design

(26) Li, C. P.; Du, M. Chem. Commun. 2011, 47, 5958–5972. (27) Munakata, M.; Kitagawa, S. Inorg. Chim. Acta 1990, 169, 225–234. (28) Wei, G.; Shen, Y. F.; Li, Y. R.; Huang, X. C. Inorg. Chem. 2010, 49, 9191–9199. (29) Zhu, W. H.; Wang, Z. M.; Gao, S. Inorg. Chem. 2007, 46, 1337–1342. (30) Chen, S. C.; Zhang, Z. H.; Huang, K. L.; Chen, Q.; He, M. Y.; Cui, A. J.; Li, C.; Liu, Q.; Du, M. Cryst. Growth Des. 2008, 8, 3437–3445. (31) Cui, P.; Dou, J.; Sun, D.; Dai, F.; Wang, S.; Sun, D.; Wu, Q. CrystEngComm 2011, 13, 6968–6971. (32) Fu, A. Y.; Jiang, Y. L.; Wang, Y. Y.; Gao, X. N.; Yang, G. P.; Hou, L.; Shi, Q. Z. Inorg. Chem. 2010, 49, 5495–5502. (33) Yang, J. X.; Zhang, X.; Cheng, J. K.; Zhang, J.; Yao, Y. G. Cryst. Growth Des. 2012, 12, 333–345. (34) Yang, D. L.; Zhang, X.; Yao, Y. G.; Zhang, J. CrystEngComm 2014, 16, 8047–8057. (35) Mitchell-Koch, J. T.; Borovik, A. S. Chem. Mater. 2003, 15, 3490–3495. (36) Sheldrick, G. M. SADABS, Program for Area Detector Adsorption Correction; Institute for Inorganic Chemistry, University of Göttingen, Göttingen, Germany 1996. (37)

Sheldrick,

G.

M.

SHELXL-97,

Program

for

Solution

of

Crystal

Structures,University of Göttingen, Göttingen, Germany, 1997. (38) Lin, J. D.; Wu, S. T.; Li, Z. H.; Du, S. W. Dalton Trans. 2010, 39, 10719–10728. (39) Cui, G.-H.; He, C.-H.; Jiao, C.-H.; Geng, J.-C.; Blatov, V. A. CrystEngComm 2012, 14, 4210–4216. (40) Yang, T.; An, J. J.; Wang, X.; Wu, D. Y.; Chen, W.; Fossey, J. S. Phys. Chem. Chem. Phys. 2012, 14, 10747–10753. (41) Julio, Z.-S.; Tiekink, E. R. T. CrystEngComm 2014, 16, 6398–6407. (42) Cheng, J. J.; Chang, Y. T.; Wu, C. J.; Hsu, Y. F.; Lin , C. H.; Proserpio, D. M.; Chen , J. D. CrystEngComm 2012, 14, 537–543. (43) Wang, X. L.; Qu, Y.; Liu, G. C.; Luan, J.; Lin, H. Y. Inorg. Chim. Acta 2013, 339, 105–111. (44) Patra, R.; Titia , H. M.; Goldberg, I. CrystEngComm 2013, 15, 2863–2872. (45) Heck, R.; Bacsa, J.; Warren, J. E.; Rosseinsky, M. J.; Bradshaw, D. CrystEngComm 2008, 10, 1687–1692. 23 ACS Paragon Plus Environment

Crystal Growth & Design

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 24 of 33

(46) Hou, L.; Zhang, J. P.; Chen, X. M. Cryst. Growth Des. 2009, 9, 2415–2419. (47) Spek, A. L. J. Appl. Crystallogr. 2003, 36, 7–13. (48) Chun, H.; Dybtsev, D. N.; Kim, H.; Kim, K. Chem. Eur. J. 2005, 11, 3521–3529. (49) Eddaoudi, M.; Kim, J.; Wachter, J. B.; Chae , H. K.; O'Keeffe, M.; Yaghi, O. M. J. Am. Chem. Soc. 2001, 123, 4368–4369. (50) Liu, J.; Zhang, H. B.; Tan, Y. X.; Wang, F.; Kang, Y.; Zhang, J. Inorg. Chem. 2014, 53, 1500–1506. (51) Cui, P.; Wu, J.; Zhao, X.; Sun, D.; Zhang, L.; Guo, J.; Sun, D. Cryst. Growth Des. 2011, 11, 5182–5187. (52) Chang, Z.; Zhang, A. S.; Hu , T. L.; Bu, X. H. Cryst. Growth Des. 2009, 9, 4840– 4846. (53) Guo, J.; Ma , J. F.; Liu , B.; Kan, W. Q.; Yang, J. Cryst. Growth Des. 2011, 11, 3609–3621. (54) Zhang, X.; Fan, L.; Sun, Z.; Zhang, W.; Li, D.; Dou, J.; Han, L. Cryst. Growth Des. 2013, 13, 792-803. (55) Wang, X.; Chang, Y. L.; Lu, J. S.; Zhang, T.; Lu, Z. H.; Wan, S. N. Adv. Funct. Mater. 2014, 24, 1911–1927.

Table of Contents (TOC)

Presented here are three Cd(II) supramolecular isomers based on a bulky 1,3-benzenedicarboxylate derivative ligand (H2IDPA). Of particular interest is that solvent molecules in fact enhance the luminescence properties but not quench it.

24 ACS Paragon Plus Environment

Page 25 of 33

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Crystal Growth & Design

Figure 1 261x196mm (300 x 300 DPI)

ACS Paragon Plus Environment

Crystal Growth & Design

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Figure 2 287x194mm (300 x 300 DPI)

ACS Paragon Plus Environment

Page 26 of 33

Page 27 of 33

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Crystal Growth & Design

Figure 3 290x192mm (300 x 300 DPI)

ACS Paragon Plus Environment

Crystal Growth & Design

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Figure 4 290x200mm (300 x 300 DPI)

ACS Paragon Plus Environment

Page 28 of 33

Page 29 of 33

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Crystal Growth & Design

Figure 5 121x51mm (300 x 300 DPI)

ACS Paragon Plus Environment

Crystal Growth & Design

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Figure 6 133x60mm (300 x 300 DPI)

ACS Paragon Plus Environment

Page 30 of 33

Page 31 of 33

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Crystal Growth & Design

Scheme 1 198x142mm (300 x 300 DPI)

ACS Paragon Plus Environment

Crystal Growth & Design

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Scheme 2 197x117mm (300 x 300 DPI)

ACS Paragon Plus Environment

Page 32 of 33

Page 33 of 33

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Crystal Growth & Design

TOC 88x34mm (300 x 300 DPI)

ACS Paragon Plus Environment