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This paper investigates the synthesis, crystal structure, thermal properties, and energetic performance of two 1D coordination polymers (CPs). The CPs, namely, [Zn(atrz)(DNBA)2(H2O)2]n (1) and [Cd(atrz)(DNBA)2(H2O)2]n (2), were designed and synthesized based on the nitrogen-rich ligand 4,4′-azobis-1,2,4-triazole (atrz) and 3,5-dinitrobenzoic acid (HDNBA) via a mixed ligand strategy using a simple and environment-friendly method. The CPs were characterized by various spectroscopic and analytical techniques along with single-crystal X-ray diffraction (SCXRD). SCXRD analysis reveals a distorted octahedral geometry around the metal ions (Zn/Cd), leading to the formation of a 1D coordination polymer while constructing a 2D structural framework through intermolecular hydrogen bonding. Both the CPs exhibit similar thermal stability but considerably differ in their heat of formation values (1 = −894.43, 2 = 1635.93 kJ mol−1). CP 2 has higher detonation velocity (7.24 km s−1) and pressure (23.67 GPa) compared to 1 (detonation velocity: 6.28 km s−1, detonation pressure: 17.57 GPa) owing to its higher heat of formation and density. Both the CPs exhibit ideal insensitivity to friction and impact stimuli, ensuring their safety during transportation and processing. The value of average activation energy obtained from isoconversion ASTM E698 for 1 and 2 was reported to be 143.8 and 168.0 kJ mol−1, respectively. This study explores the development of energetic CPs through the mixed ligand strategy based on the atrz ligand and incorporating HDNBA as the co-ligand to reduce the sensitivity while maintaining the comparable energetic performance of previously reported atrz-based complexes. This paper also highlights the potential use of CPs as explosives by demonstrating higher energetic performance. [ABSTRACT FROM AUTHOR]

A series of crystalline porous organic framework materials (CPOFs), such as metal–organic frameworks (MOFs), covalent organic frameworks (COFs), and hydrogen bonded organic frameworks (HOFs), have received extensive attention due to their tunable structure and various excellent applications. Postsynthetic modification (PSM) is a facile and effective method to introduce functional species into channels of MOFs, COFs, and HOFs, which includes coordinated PSM, covalent PSM, ion exchange, ligand exchange, and so on. Trivalent lanthanide (Ln3+) ions as great luminescent species can be decorated on CPOFs based on coordinated PSM, and other PSM strategies are also adopted for better fabrication of Ln3+ functionalized CPOF materials. At present, lots of examples of Ln@MOF/COF/HOF luminescent materials and devices have been proposed for various optical applications. Their tunable structure and induced luminescent Ln3+ ions will provide targeted luminescence properties for MOFs, COFs, and HOFs. In this review, the design and fabrication of Ln@MOF/COF/HOF luminescent materials and devices are elaborated systematically, the discussion key point being mainly concerned on the design ideas and fabrication methods of recent Ln@MOF/COF/HOF luminescent materials. It's notable that many fabrication methods for Ln@MOF/COF/HOF films, including FTO, ITO, ZnO, paper, hydrogel-based films, and fabric, have also been provided. [ABSTRACT FROM AUTHOR]

A careful selection of organic and inorganic components enables the production of unusual structure types with promising practical properties by facile syntheses. In this paper, we describe novel supramolecular architectures comprising organic adamantane-like divalent building blocks and iodide or polyiodide anions. Highly acidic conditions facilitated the formation of a doubly protonated organic ligand out of 5,7-dimethyl-1,3-diazaadamantane that generates three different crystal structures with inorganic counterions. In these structures, cationic substructures are constructed by transforming neutral organic ligands into [(C10N2H20)I]+ or [(C10N2H20)(H2O)]2+ cations, which crystallize with charge-compensating iodine-based anions of different complexities. All three crystal structures are characterized by various noncovalent forces, ranging from strong (N)H⋯I, (O)H⋯I, and (N)H⋯O hydrogen bonds to secondary and weak I⋯I interactions. Raman and diffuse reflectance spectroscopy as well as DFT calculations were employed to describe the electronic structures and optical properties of new supramolecular architectures, with particular attention to the role of non-covalent interactions. [ABSTRACT FROM AUTHOR]

The synthesis, crystallisation and detailed description of the crystal structure of the THF solvates of four halogen (F, Cl, Br and I) derivatives of dianthranilide (5H,11H-dibenzo[b,f][1,5]diazocine-6,12-dione) have been reported. The influence of the halogen size on the conformation of the halogen derivative, the overall supramolecular architecture including the existing scheme of intermolecular interactions and the selected energy issues have been discussed in detail. The solvates which are described in this paper exhibit an interesting arrangement of molecules in their crystals resembling a "honeycomb". The variety of interactions between the respective molecules, including hydrogen bonds, halogen-mediated noncovalent interactions and π–π contacts, makes them an attractive target for crystallographic studies. The results of our analysis may lead to a better understanding of the role of a halogen functional group in the rational design of specific multicomponent crystalline networks based on compounds consisting of two substituted phenyl rings separated by a fused heterocyclic moiety. [ABSTRACT FROM AUTHOR]

In this paper, three isostructural 1D lanthanide complexes, [Ln(dppc)(H2O)4]n·2nH2O (Ln = Eu, Tb and Eu0.501Tb0.499, named 1-Eu, 2-Tb and Eu0.501Tb0.499), based on 3-(2,4-dicarboxylate phenyl)-2-pyridinecarboxylic acid (H3dppc) have been synthesized and characterized by elemental analysis, IR, PXRD, TG and X-ray crystallography. The complexes exhibit a 1D chain structure, which is further linked into a 3D supramolecular framework by hydrogen bonds. Tuneable emission colour of Eu0.501Tb0.499 is realized by adjusting the excitation wavelength. The sensing properties of 1-Eu and 2-Tb towards Fe3+ and aniline indicate that the two complexes have almost the same superior sensitivity and low detection limit for Fe3+ in aqueous solution, while they have different detection abilities for aniline in DMF solvent. The different detection abilities were discussed by means of PXRD, UV-vis, luminescence lifetimes and molecular surface calculations (Hirshfeld surface analysis and 2D fingerprint plots). [ABSTRACT FROM AUTHOR]

3-Phenylpyrrolidine-2,5-dione (PPD) is the pharmacologically relevant metabolite of the clinically used antiepileptic drug phensuximide. In 1973, Gy. Argay and A. Kálmán, Acta Crystallogr., Sect. B: Struct. Crystallogr. Cryst. Chem., 1973, 29, 636–638 described an orthorhombic modification (polymorph I) of rac-PPD with one molecule in the asymmetric unit (Pna21; Z′ = 1) and mentioned the existence of another, monoclinic modification (polymorph II). By varying the crystallization conditions, we were able to obtain diffraction-quality crystals of the monoclinic polymorph II (P21/c; Z′ = 2) and of novel triclinic polymorph III (P1¯; Z′ = 3). In this paper, we report a detailed structural comparison of these variable-Z′ polymorphs of rac-PPD. We found a remarkable diversity of intermolecular interactions (medium-strength N–H⋯O hydrogen bonds, weak C–H⋯O hydrogen bonds, carbonyl–carbonyl interactions, edge-to-face aromatic–aromatic interactions). We also explored the relative stability of these polymorphs (as indicated by crystal lattice energies and thermal analysis data). Our results are expected to aid in developing a better understanding of solid-state structure of cyclic imide-based antiepileptic drugs. [ABSTRACT FROM AUTHOR]

In this paper, a series of D–π–A type benzo[e]indolium salts with highly efficient nonlinear optical performance has been synthesized. Out of the three new benzo[e]indolium salts, (E)-2-(2-hydroxy-3-methoxystyryl)-1,1,3-trimethyl-1H-benzo[e]indol-3-ium iodide (HMTB-1) and (E)-2-(2-hydroxy-4-methoxystyryl)-1,1,3-trimethyl-1H-benzo[e]indol-3-ium iodide (HMTB-2) possess SHG properties, and their maximum powder second harmonic generation (SHG) efficiency is around 0.6 times that of DAST (4-N,N-dimethylamino-4′-N′-methyl-stilbazolium tosylate) at a non-resonant wavelength of λ = 1570 nm. Single crystals of the two noncentrosymmetric salts were successfully grown by using a slow cooling method, and we were able to obtain very large bulk single crystals, about 17 mm × 9 mm × 3 mm, of HMTB-2. X-ray crystallographic analysis indicated that both of the new salts belong to the monoclinic space group Cc (point group m, Z = 4). HMTB-1 forms a noncentrosymmetric phase with methanol through hydrogen bonding. [ABSTRACT FROM AUTHOR]

This paper addresses a series of recent investigations into crystalline porphyrin-based assemblies directed by non-covalent and non-coordinative interactions. It describes attractive design strategies for the formulation of multi-dimensional aggregates of suitably activated poly-topic porphyrins, without the use of metal ion connectors. The major part of the discussion relates to open porphyrinic networks supported by cooperative halogen bonding and hydrogen bonding interaction synthons, highlighting the crystal-engineering toolbox available to this end. [ABSTRACT FROM AUTHOR]