Search

• Four triazole derivatives were synthesized and characterized by the structural investigation. • Detail structural analysis provides an understanding of the effect of various substituent on the supramolecular construct. • The nature and energetics of the intermolecular interactions involved in 3D networks have been discussed and presented via inputs from different computational approaches. • Along with strong H-bonds, weak intermolecular interactions also contribute comprehensively towards the overall stability of these crystal structures. This manuscript comprehensively examines four triazole derivatives using Hirshfeld surface and fingerprint analysis, PIXEL energy for molecular pairs, lattice energies for crystal packing, atoms-in-molecules (AIM) topological analysis, and noncovalent interaction (NCI) plots for intermolecular interactions. The fingerprint plots of the Hirshfeld surface analysis provide a quantitative picture of various substituent effects on the noncovalent interactions that contribute to the crystal packing stabilization of these four structures (TN1 – TN4). The PIXEL method provides the intermolecular interaction energies for the molecular dimers observed in these structures. The nature and strength of intermolecular interactions at the (3, -1) bond critical point have been studied using the approach of atoms-in-molecules (AIM) via a topological analysis of the electron density distribution. The topology parameters suggested that the intermolecular interactions are classified as closed-shell interactions, and NCI plots were employed to identify the nature of the involved noncovalent interactions. Therefore, a detailed computational analysis renders insights into the electronic characteristics of different noncovalent interactions in the solid state of the structures in the current investigation. [ABSTRACT FROM AUTHOR]

• The molecular structures of two synthesized Cu(II)-PDA complexes have been studied using single-crystal X-ray diffraction. • Supramolecular networks in the crystal structures have been explored. • The noncovalent interactions are quantified through hirshfeld surface analysis. • AIM analysis and topological parameters characterize the intermolecular interactions. • Visual representation of noncovalent interactions is performed by NCI plot index. The structural study of two synthesized Cu-PDA (Cu = Copper(II), PDA = deprotonated Pyridine-2,6-dicarboxylic acid) complexes has been carried out using single-crystal X-ray diffraction where complex (1) [Cu(PDA)(H 2 O) 2 ] exhibits one-dimensional (1D) and two-dimensional (2D) supramolecular assemblies and complex (2) [Cu(PDA)(H 2 PDA)]·H 2 O exhibits 1D, 2D, and 3D (three-dimensional) supramolecular networks in their solid-state structure with the aid of intermolecular noncovalent interactions. Lone pair···π/π···lone pair networks are exclusively found in both complex (1) and (2). The intermolecular interactions are characterized through Hirshfeld surface analysis and quantified by 2D fingerprint plot. The noncovalent interactions are further characterized by Bader's theory of 'Atoms in Molecules' (AIM) and 'noncovalent interaction' (NCI) plot and the topological parameters at bond critical points (BCPs) have been evaluated. Therefore, the energetic factors to the stabilization of the crystal structure observed experimentally have been obtained by the computational calculations. [ABSTRACT FROM AUTHOR]

• Comparison of structural diversity of PDA and its di-hydrate has been explored. • The lattice energy of PDA outperformed 43.3% than its di-hydrate. • Electrostatic forces dominate in PDA and dispersion forces in its di-hydrate. • AIM's topological parameters reveal closed-shell nature of noncovalent interactions. • RBG color scheme of NCI analysis characterizes the nature of noncovalent interactions. Crystals of pyridine-2,6-dicarboxylic acid (1) have been structurally characterized through single-crystal X-ray diffraction analysis and compared with pyridine-2,6-dicarboxylic acid dihydrate ((2) retrieved from CSD), and explore the solid-state networks. In the solid state, compound (1) exhibits both hydrogen bonding and π···π interactions, while the supramolecular network of compound (2) is stabilized only by hydrogen bonding interactions. The non-covalent interactions are characterized by various computational studies such as Hirshfeld surface analysis, Bader's 'Atoms in Molecules' (AIM) theory, and 'Non-covalent interaction' (NCI) plot analysis. Hirshfeld surfaces and corresponding 2D fingerprint plots reveal the contribution of non-covalent interactions involved in the structure. Lattice energy framework calculations also are carried out for both compounds. The topological parameters of the AIM analysis suggest the 'closed-shell' nature of the non-covalent interactions. Further, NCI plots and scatter graphs (RDG vs sign (λ 2)ρ) characterize non-covalent interactions with a color scheme. [Display omitted] [ABSTRACT FROM AUTHOR]

Herein we report the synthesis and detailed structural characterization of two new centrosymmetric dinuclear coordination compounds of Pb(II) [Pb2L2(NCS)4] (1) and [Pb2L2(NO3)4]∙2MeOH (2), using the organic ligand 1,2-diphenyl-1,2-bis((methyl(pyridin-2-yl)methylene)hydrazono)ethane (L). In both complexes, each subunit [PbLX2 (X = NO3 or NCS)] adopts a quasi-aromatic Möbius metal chelate structure. Each ligand L is coordinated in a tetradentate coordination mode to Pb(II), yielding the 12π electron chelate ring via two pyridyl-imine units. In compound (1), the coordination sphere is completed by one disordered N,S-coordinated thiocyanate anion and two μ1,1-bridging N-coordinated thiocyanate anions. In compound (2), the coordination sphere of Pb(II) is completed by two monodentate and two bidentate nitrato ligands (two of them acting as bridging ligands). Crystal packing of both compounds is stabilized by intermolecular hydrogen bonds, intra- and intermolecular C–H∙∙∙π interactions. The Hirshfeld molecular surfaces of (1) and (2) demonstrate that their packing is dominated by C–H∙∙∙O/N/S interactions as well as by far less favored H∙∙∙H contacts. [ABSTRACT FROM AUTHOR]

The supramolecular frameworks of two metal complexes with 1,3-diamino-2-hydroxypropanetetraacetic acid (H 4 Hpdta) have been explored in the context of crystal engineering, and the noncovalent interactions are further characterized by Bader's quantum theory of "atoms-in-molecules" (QTAIM), Noncovalent Interaction (NCI) plot index and Scatter plot. [Display omitted] A new 1,3-diamino-2-hydroxypropanetetraacetate copper complex (1) [{Cu(Hpdta)}{Cu(H 2 O) 6 }] has been synthesized and structurally characterized by single crystal X-ray diffraction and compared with a similar cobalt complex (2) of H 4 Hpdta (H 4 Hpdta = 1,3-diamino-2-hydroxypropanetetraacetic acid) retrieved from CSD (CSD ref code: TELBAN) with a detailed analysis of intermolecular interactions. X-ray crystallography reveals that both complexes are stabilized through C−H⋯O and O−H⋯O interactions generating different supramolecular networks. Detailed analysis of Hirshfeld surfaces and 2D fingerprint plot has been carried out for the title complexes to quantify the intermolecular interactions. Further, the noncovalent interactions are characterized through the Bader's theory of 'Atoms in Molecules' (AIM) and noncovalent interaction (NCI) plot index. At the bond critical point (BCP), the electron density (ρ BCP) and the Laplacian of electron density ( ∇ 2 (ρ BCP)) differ significantly for strong and weak noncovalent interactions. The dissociation energies are evaluated for validating the intermolecular interactions required to stabilize the complexes. The analysis of topological parameters extracted from AIM calculation characterized the interactions as closed-shell interactions. [ABSTRACT FROM AUTHOR]

• New binuclear monooxo, dioxo and tetramolecular tetraoxo bridging molybdenum(VI) complexes with ONS donor ligand has been synthesized. • Complexes give rise to interesting supramolecular architectures. • Hirshfeld surface analysis and fingerprint plots have been done for better understanding of non-covalent interactions. • 'Atoms in molecules' (QTAIM) along with 'non-covalent interaction' (NCI) plot index analyses have also been carried out. New Binuclear monooxo, Mo 2 O 4 L 2 1(H 2 O)CHCl 3 (1), tetranuclear tetraoxo, Mo 4 O 8 L 4 1 (2) and binuclear dioxo, Mo 2 O 4 L 2 2 (3) bridged molybdenum(VI) complexes have been synthesized using two diprotic tridentate ONS donor Schiff base ligands H 2 L1 and H 2 L2 (H 2 L1 = S - benzyl-β-N-(2-hydroxyphenyl) methylene dithiocarbazate and H 2 L2 = S - benzyl-β-N-(5‑bromo-2-hydroxyphenyl) methylene dithiocarbazate. All the three complexes have been characterized by elemental analyses and IR, UV–vis and 1H NMR spectroscopies and their crystal structures were solved by single crystal X-ray diffraction technique. Complexes (1) and (3) crystallized in triclinic space group P-1 and complex (2) in monoclinic space group P2 1 /n. Complexes 1, 2 and 3 exhibit distorted octahedral geometry around Mo(VI) center. X-ray crystallography reveals that in the crystal packing of the complexes C–H···O, O–H···O, O–H···N, C–X···π (X = Br) and π···π stacking interactions cooperatively take part. A detailed analysis of Hirshfeld surfaces and fingerprint plots facilitates a comparison of intermolecular interactions which are crucial in building different supramolecular architectures of three molybdenum complexes. Crystal structure analysis supported with the Hirshfeld surface and fingerprint plots enabled the identification of the significant intermolecular interactions. The intermolecular interactions are further characterized by analyzing the topological parameters through Bader's theory of 'atoms in molecule' (QTAIM) along with the 'non-covalent interaction' (NCI) plot index. The investigation of topological parameters of electron density at the (3, −1) bond critical point classified the interactions as 'closed-shell' interactions. Using two diprotic tridentate ONS donor Schiff base ligands (H 2 L1 and H 2 L2), new binuclear monooxo, Mo 2 O 4 L 2 1(H 2 O)CHCl 3 (1), tetramolecular tetraoxo, Mo 4 O 8 L 4 1 (2) and binuclear dioxo, Mo 2 O 4 L 2 2 (3) bridging molybdenum(VI) complexes have been synthesized and structurally characterized. Complexes 1–3 give rise to interesting supramolecular architectures. Hirshfeld surface, fingerprint plots and AMI (atoms in molecules) analysis has also been done in order to acquire a better understanding of non-covalent interactions. [Display omitted] [ABSTRACT FROM AUTHOR]

• Microwave irradiation and novel imidazopyridine-based compound. • 1H NMR, 13C NMR, FTIR, HRMS, SXRD analysis. • Supramolecular self-assembly. • Hirshfeld surface and fingerprint plot analysis. • Bader's theory of 'atoms in molecules' (AIM) and 'Non-covalent interaction (NCI) plot index. Synthesis of 5-(4-methoxyphenyl)-7-phenyl-2-(pyridin-2-yl)imidazo[1,2- a ]pyridine-8-carbonitrile has been carried out by the reaction between 1-(pyridin-2-yl)ethanone and 2-amino-6-(4-methoxyphenyl)-4-phenylnicotinonitrile under microwave irradiation. The synthesized compound has been characterized on the basis of spectroscopic data such as 1H NMR, 13C NMR, FTIR, HRMS, and single crystal XRD. The XRD data reveals that the solid-state structure of the compound belongs to the triclinic system of the space group P 1 ‾ and is stabilized through C–H⋯N, C–H⋯π, and π⋯π interactions. Quantification of the non-covalent interactions is analyzed through Hirshfeld surface analysis. The non-covalent interactions are characterized through Bader's Theory of "Atoms-in-Molecules" (AIM) and the "Non-covalent Interaction" (NCI) plot index. The analysis of topological parameters of charge density at the (3, −1) bond critical points (BCPs) classified the interactions as "closed-shell" interactions. A theoretical study on Non-Covalent Interactions in novel imidazopyridine derivative for obtaining insights into the future design of better molecules have been undertaken. [Display omitted] [ABSTRACT FROM AUTHOR]