Hierarchically Organized Cocrystal of Tetra-Anionic Porphyrin and Di-Cationic Viologen: Ion Conformations, Supramolecule Interactions, and Porphyrin Arrays.

Ionic co-assembly of tetra-anionic porphyrins has been extensively researched in the construction of hierarchically organized architectures with potential application value in organic semiconductors, sunlight catalysts and supramolecular chirality systems. However, such architectures are difficult to grow to a size suitable for single-crystal X-ray diffraction (SCXRD); the lack of single-crystal structures of these architectures leads to challenges in gaining deeper comprehension about that. This study reports a hierarchically organized cocrystal of meso-tetra(4-sulfonato-phenyl)-porphyrin (TSPP4- ) and N, N'-diethyl-viologen (DEV2+ ), wherein wave-like and saddle-like TSPP4- ions co-aggregate at a stoichiometric ratio of 1 : 2 to form unique porphyrin arrays; the spectrum characteristics and calculated coulombic exciton coupling energy show that these porphyrin arrays are J-aggregates. We prove that the distortion of porphyrin ring of TSPP4- strongly correlates with the deflection of its phenyl groups. The crystal comprises six different ionic conformations, and the multiplicity of ionic conformation leads to intricate supramolecular interactions.

Organic-Inorganic Two-Dimensional Hybrid Networks Constructed from Pyridine-4-Carboxylate-Decorated Organotin-Lanthanide Heterometallic Antimotungstates.

Six organic-inorganic hybrid pyridine-4-carboxylate-decorated organotin (OT)-lanthanide (Ln) heterometallic antimotungstates [Ln(H2O)6(pca)]H[Sn(CH3)2(H2O)]3[B-ß-SbW9O33]·12H2O [Ln = La3+ (1), Ce3+ (2), Pr3+ (3), Nd3+ (4), Sm3+ (5), Eu3+ (6); Hpca = isonicotinic acid] have been prepared with the help of the structure-directing effect of the trivacant [B-α-SbW9O33]9- segment toward [(CH3)2Sn]2+ and Ln3+ ions in an acidic water medium. The prominent architecture characteristic is that their structural units consist of a trivacant [B-ß-SbW9O33]9- segment stabilized by three [Sn(CH3)2(H2O)]2+ groups and a [Ln(H2O)6(pca)]2+ cation, which are interconnected to propagate an intriguing two-dimensional (2D) network. For all we know, 1-6 stand for the first 2D OT-Ln heterometallic polyoxometalates. Furthermore, luminescence performances of solid-state 3-6 were deeply surveyed at ambient temperature. Energy migration from [B-ß-SbW9O33]9- and pca- to Sm3+ centers in 5 was also studied. Comparative studies demonstrate that the contribution of [B-ß-SbW9O33]9- sensitizing the emission of Sm3+ is prominently larger than that of pca- sensitizing the emission of Sm3+ in the emission process of 5. Most interestingly, 6 as a fluorescence probe exhibits high selectability and sensitivity for recognizing Zn2+ and Cu2+ in water.

Highly Efficient Multicolor-Emitting Tetraphenylethylene-Based Organic Salts with Commercialization Prospects.

Since the discovery of aggregation-induced emission from tetraphenylethylene derivatives, various methods have been explored to prepare highly efficient multicolored luminescent materials. Herein, we report a simple and efficient strategy for constructing luminescent organic salts of the tetracationic luminogen, tetrapyridinium-tetraphenylethylene (T4Py-TPE4+), combined with seven di- and tetra-anionic aromatic sulfonate ligands. When aqueous solutions of the cationic luminogen and the anionic ligands were mixed, they rapidly aggregated into organic salts within seconds to minutes, giving yields of up to >90%. This was accompanied by an increase in the emission efficiency from ∼58% to almost 100%, and the ability to tune the emission color between 511 and 586 nm. These improvements were mainly attributed to the strong electrostatic attractions between the cation and anions, which resulted in the formation of a rigid hydrophobic network of the T4Py-TPE4+ luminogen with various π-conjugation lengths. Because these compounds are commercially available, this method opens the possibility of fabricating novel light-emitting materials for device fabrication and research.

Organic-inorganic hybrid 1-D double chain heteropolymolybdates constructed from plenary Keggin germanomolybdate anions and hepta-nuclear Cu-RE-pic heterometallic clusters.

Two unprecedented organic-inorganic hybrid 1-D double chain germanomolybdates containing hepta-nuclear Cu-RE-pic heterometallic clusters [NH4]2[RE(H2O)5]2[Cu(pic)2]2[Cu(pic)2(H2O)2]3[α-GeMo12O40]2·22H2O [RE = La3+ (1), Ce3+ (2), and Hpic = 2-picolinic acid] were successfully obtained by the stepwise self-assembly strategy via the conventional solution method. The most striking structural feature of 1 and 2 is that the two plenary Keggin [α-GeMo12O40]4- polyoxoanions are joined by an organic-inorganic hybrid hepta-nuclear Cu-RE-pic {[RE(H2O)5]2[Cu(pic)2(H2O)2]3[Cu(pic)2]2}6+ heterometallic moiety. What is more interesting is that their adjacent structural units are connected together by {Cu(pic)2} bridges, forming a 1-D extended double chain architecture. Furthermore, the adsorption capacity of 1 toward dyes in aqueous solutions was deeply investigated. It is fascinating that 1 shows a good adsorption capacity toward basic violet 3 (BV 3) in aqueous solutions and the adsorption kinetics conforms to the second-order kinetic model.

Ligand-Controlled Assembly of Heteropolyoxomolybdates from Plenary Keggin Germanomolybdates and Cu-Ln Heterometallic Units.

By virtue of combining an in-situ assembly process with a stepwise synthesis in conventional aqueous solution, two series of unique organic-inorganic hybrid heteropolyoxomolybdates were constructed from plenary Keggin germanomolybdates and Cu-Ln heterometallic units and fully characterized: [H2 INA]2 H8 [LnCu(INA)4 (H2 O)6 ]2 [α-GeMo12 O40 ]3 ⋅52 H2 O (Ln=La3+ (1), Ce3+ (2), Pr3+ (3), Nd3+ (4), Sm3+ (5), Eu3+ (6); HINA=isonicotinic acid) and (NH4 )[Cu(PA)2 ][Cu(PA)2 Ln(H2 O)8 ][α-GeMo12 O40 ]⋅10 H2 O (Ln=Nd3+ (7), Sm3+ (8), Eu3+ (9); HPA=picolinic acid). The most remarkable structural characteristic of compounds 1-6 was that their molecular units were defined by three discrete plenary Keggin [α-GeMo12 O40 ]4- polyoxoanions and two organic-inorganic hybrid heterometallic [LnCu(INA)4 (H2 O)6 ]+ moieties, whereas compounds 7-9 exhibited a nice-looking 1D chain-like structure that was built from plenary [α-GeMo12 O40 ]4- polyoxoanions, pendent [Cu(PA)2 ] complexes, and bridging {[Cu(PA)2 ][Ln(H2 O)8 ]}3+ heterometallic groups. Notably, two different pyridine carboxylic acid ligands led to the discrepancy between the two structure types. To the best of our knowledge, compounds 1-9 constitute the first examples of plenary Keggin heterometallic germanomolybdates that include Cu-Ln-organic subunits. Further studies revealed that compounds 3 and 8 exhibited fast adsorption capacity for cationic dyes methylene blue (MB) and rhodamine B (RhB) in water. Moreover, compounds 3 and 8 could quickly and selectively adsorb MB from a mixture of MB/methyl orange (MO) or MB/azophloxine (Apo).