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Controlling the optical activity of halide perovskite materials through modulation of the coordination configurations of the metal ions is important. Herein, a novel manganese‐based halide, specifically diaquatetrakis(methyldiphenylphosphine oxide)manganese(II) tetrachloridomanganate(II), [Mn(C13H13OP)4(H2O)2][MnCl4] or [Mn(MDPPO)4(H2O)2][MnCl4] (MDPPO is methyldiphenylphosphine oxide), was synthesized through the solvothermal reaction of MnCl2 with the neutral molecule MDPPO. In this compound, [Mn(MDPPO)4(H2O)2]2+ acts as the cation, while [MnCl4]2− serves as the anion, enabling the co‐existence of tetrahedral and octahedral structures within the same system. Remarkably, the compound exhibits efficient red‐light emission at 662 nm, distinct from the green‐light emission typically observed in MnX4‐based halides. Theoretical calculations show that the red emission comes from the charge transfer from the MDPPO to the Mn2+ of [MnCl4]2−. This work provides a new perspective for the design and synthesis of red‐light‐emitting manganese‐based halides with unique structures. [ABSTRACT FROM AUTHOR]

Although the crystals of coordination polymer {[CuCl(μ-O,O'-L-Br2Tyr)]}n (1) (L-Br2Tyr = 3,5-dibromo-L-tyrosine) were formed under basic conditions, crystallographic studies revealed that the OH group of the ligand remained protonated. Two adjacent [CuCl(L-Br2Tyr)] monomers, bridged by the carboxylate group of the ligand in the syn-anti bidentate bridging mode, are differently oriented to form a polymeric chain; this specific bridging was detected also by FT-IR and EPR spectroscopy. Each Cu(II) ion in polymeric compound 1 is coordinated in the xy plane by the amino nitrogen and carboxyl oxygen of the parent ligand and the oxygen of the carboxyl group from the symmetry related ligand of the adjacent [Cu(L-Br2Tyr)Cl] monomer, as well as an independent chlorine ion. In addition, the Cu(II) ion in the polymer chain participates in long-distance intermolecular contacts with the oxygen and bromine atoms of the ligands located in the adjacent chains; these intramolecular contacts were also supported by NCI and NBO quantum chemical calculations and Hirshfeld surface analysis. The resulting elongated octahedral geometry based on the [CuCl(L-Br2Tyr)] monomer has a lower than axial symmetry, which is also reflected in the symmetry of the calculated molecular EPR g tensor. Consequently, the components of the d-d band obtained by analysis of the NIR-VIS-UV spectrum were assigned to the corresponding electronic transitions. [ABSTRACT FROM AUTHOR]

This study describes the synthesis of novel chalconethiocarbohydrazones derived from 2′-hydroxychalcone and thiocarbohydrazide as potential drugs. The monothiocarbohydrazone (M1) and bisthiocarbohydrazone (M2) compounds were obtained by condensing thiocarbohydrazide with 2′-hydroxychalcone [1-(2-hydroxyphenyl)−3-phenyl-2-propen-1-one] at 1/1 and 1/2 mol ratios. The synthesized compounds were characterized by elemental analysis, 1H NMR, FT-IR and UV-Vis spectroscopic techniques. The crystal structures of M1 and M2 were solved using single crystal X-ray diffraction method. The total antioxidant capacities of synthesized thiocarbohydrazones were determined by Cupric Reducing Antioxidant Capacity (CUPRAC) method. It was investigated also the radical scavenging activities of these compounds with 2,2-Diphenyl-1-picrylhydrazyl (DPPH) method. When compared to standard compound Trolox, both of the compounds showed good antioxidant activity. For the new compounds, Conceptual Density Functional Theory (CDFT) computations were performed to compute important quantum chemical reactivity descriptors. The chemical reactivities of the studied chemical systems were compared via well-known electronic structure rules of CDFT. Experimentally determined antioxidant activities of the synthesized compounds were supported with Molecular Docking analyses. [ABSTRACT FROM AUTHOR]

Two series of rare earth coordination compounds have been synthesized (Na[RE(L4)] (labeled as 1RE) and PPh4[RE(L4)] (labeled as 2RE), where RE = Y3+, Eu3+, Tb3+, L = 2,2,2-trichloro-N-(diphenylphosphoryl)acetamide) to determine the possibility of modifying their photophysical and magnetical properties by changing the counterion. The crystal structure of 1RE was determined based on the single-crystal X-ray diffraction and the crystal structure of 2RE was determined based on quantum chemistry computational procedures. Characterization of the physicochemical properties of the compounds was carried out using differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), 1H and 31P NMR spectroscopy as well as FT-IR, absorption and luminescence spectroscopy in the temperature range of 300 - 77 K. The rate constants of radiative (Arad) and non-radiative (Anrad) transitions, intrinsic (QLnLn) and overall (QLnL) emission quantum yields, sensitization efficiency (ηsens), the experimental and theoretical intensity parameters (Ωλ), the forward (WS, WT) and backward (WbS, WbT) intramolecular energy transfer (IET) rates were determined. Magnetic properties of Tb3+ compounds were studied in a constant field of 0.5 T in the temperature range of 1.8–300 K. Dynamic AC magnetic susceptibility measurements were carried out as a function of temperature and frequency for 1Tb and 2Tb. Only in the case of 2Tb, in the presence of an external DC field, a slight temperature dependence of in-phase χ′ and out-of-phase χ'' susceptibility was recorded. Based on experimental and theoretical results, the significant effect of counterion on the photophysical and magnetic properties of RE chelates has been demonstrated and clarified, providing valuable guidance for the design of bifunctional electromagnetic radiation converters.

A new copper(I) complex, [Cu2(L)2dppm](PF6)2 (1) [L = 3-(2-Pyridyl)-5,6-diphenyl-1,2,4-triazine and dppm: Bis(diphenylphosphino)methane], was prepared and characterized by IR, 1H-NMR, 31P-NMR spectroscopy, elemental and thermogravimetric analysis, and a single-crystal X-ray diffraction technique. Complex 1 is a dinuclear compound, showing that L and dppm act as tridentate and bidentate chelating ligands, respectively. The two Cu(I) atoms exhibit a distorted tetrahedral coordination sphere embedded in N3P environments. The supramolecular interactions in the solid-state structure are characterized by C−H···N, C−H···F, C-H···π and π···π intermolecular interactions, which we studied using Hirshfeld surface and fingerprint tools. Additionally, the complex was studied experimentally using UV–Vis spectroscopy and cyclic voltammetry, and theoretical studies with time-dependent density functional theory (TD-DFT) were performed. Moreover, the optical and electrochemical properties were studied, focusing on the band gap. Compound 1 was used as a co-sensitizer in a dye-sensitized solar cell, showing a good photovoltaic performance of 2.03% (Jsc = 5.095 mAcm−2, Voc = 757 mV, and FF = 52.7%) under 100 mW cm−2 (AM 1.5G) solar irradiation, which is similar to that of DSSC, which was only sensitized by N719 (2.2%) under the same condition. [ABSTRACT FROM AUTHOR]

Although the crystals of coordination polymer {[CuCl(μ-O,O’-L-Br2Tyr)]}n (1) (L-Br2Tyr = 3,5-dibromo-L-tyrosine) were formed under basic conditions, crystallographic studies revealed that the OH group of the ligand remained protonated. Two adjacent [CuCl(L-Br2Tyr)] monomers, bridged by the carboxylate group of the ligand in the syn-anti bidentate bridging mode, are differently oriented to form a polymeric chain; this specific bridging was detected also by FT-IR and EPR spectroscopy. Each Cu(II) ion in polymeric compound 1 is coordinated in the xy plane by the amino nitrogen and carboxyl oxygen of the parent ligand and the oxygen of the carboxyl group from the symmetry related ligand of the adjacent [Cu(L-Br2Tyr)Cl] monomer, as well as an independent chlorine ion. In addition, the Cu(II) ion in the polymer chain participates in long-distance intermolecular contacts with the oxygen and bromine atoms of the ligands located in the adjacent chains; these intramolecular contacts were also supported by NCI and NBO quantum chemical calculations and Hirshfeld surface analysis. The resulting elongated octahedral geometry based on the [CuCl(L-Br2Tyr)] monomer has a lower than axial symmetry, which is also reflected in the symmetry of the calculated molecular EPR g tensor. Consequently, the components of the d-d band obtained by analysis of the NIR-VIS-UV spectrum were assigned to the corresponding electronic transitions.

The development of high‐power solid‐state lasers is in urgent need of infrared (IR) nonlinear optical (NLO) materials with wide band gaps and high laser‐induced damage thresholds (LIDTs). Herein, a new compressed chalcopyrite‐like IR NLO crystal (Na0.74Ag1.26)BaSnS4 was successfully synthesized using a facile high‐temperature solid‐state method. Its structure can be considered as a variant of chalcopyrite AgGaS2 (AGS)‐type ones. It features a three‐dimensional framework constructed by corner‐sharing {[(Na/Ag)S4]7−}∞ layers and isolated SnS4 tetrahedra with negative cavities occupied by counter ion Ba2+. (Na0.74Ag1.26)BaSnS4 exhibits phase‐matchable moderate SHG response (0.31 × AGS), wide band gap (3.70 eV), and high LIDT (6.44 × AGS). Theoretical calculations reveal that the NLO response of (Na0.74Ag1.26)BaSnS4 is mainly originated from the synergetic effects of AgS4 and SnS4 tetrahedra, and the inclusion of alkaline and alkaline earth metals is responsible for the wide band gap and high LIDT. Moreover, the discovery of this chalcopyrite‐like compound will provide a feasible design strategy for the exploration of new promising IR NLO materials. [ABSTRACT FROM AUTHOR]

A new copper(I) complex, [Cu2(L)2dppm](PF6)2 (1) [L = 3-(2-Pyridyl)-5,6-diphenyl-1,2,4-triazine and dppm: Bis(diphenylphosphino)methane], was prepared and characterized by IR, 1H-NMR, 31P-NMR spectroscopy, elemental and thermogravimetric analysis, and a single-crystal X-ray diffraction technique. Complex 1 is a dinuclear compound, showing that L and dppm act as tridentate and bidentate chelating ligands, respectively. The two Cu(I) atoms exhibit a distorted tetrahedral coordination sphere embedded in N3P environments. The supramolecular interactions in the solid-state structure are characterized by C−H···N, C−H···F, C-H···π and π···π intermolecular interactions, which we studied using Hirshfeld surface and fingerprint tools. Additionally, the complex was studied experimentally using UV–Vis spectroscopy and cyclic voltammetry, and theoretical studies with time-dependent density functional theory (TD-DFT) were performed. Moreover, the optical and electrochemical properties were studied, focusing on the band gap. Compound 1 was used as a co-sensitizer in a dye-sensitized solar cell, showing a good photovoltaic performance of 2.03% (Jsc = 5.095 mAcm−2, Voc = 757 mV, and FF = 52.7%) under 100 mW cm−2 (AM 1.5G) solar irradiation, which is similar to that of DSSC, which was only sensitized by N719 (2.2%) under the same condition.

8-Hydroxyquinolin-5-sulfonic acid (8HQSA) was combined with 3-pyridineboronic acid (3PBA) or 4-pyridineboronic acid (4PBA) to give two zwitterionic monoboron complexes in crystalline form. The compounds were characterized by elemental analysis, single-crystal X-ray diffraction studies, and IR, 1H NMR, UV-Visible, and luminescence spectroscopy. The analyses revealed compounds with boron atoms adopting tetrahedral geometry. In the solid state, the molecular components are linked by charge-assisted (B)(O−H⋯−O(S) and N+−H⋯O(S) hydrogen bonds aside from C−H⋯O contacts and π⋯π interactions, as shown by Hirshfeld surface analyses and 2D fingerprint plots. The luminescence properties were characterized in terms of the emission behavior in solution and the solid state, showing emission in the bluish-green region in solution and large positive solvatofluorochromism, caused by intramolecular charge transfer. According to TD-DFT calculations at the M06-2X/6-31G(d) level of theory simulating an ethanol solvent environment, the emission properties are originated from π-π * and n-π * HOMO-LUMO transitions. [ABSTRACT FROM AUTHOR]

New zinc(II) Schiff base complexes (Z1 and Z2) were prepared through the treatment of ONNO tetradentate Schiff base ligands (H2L1 and H2L2) with zinc acetylacetonate. Elemental analysis (C, H and N) and other spectroscopic techniques such as FT-IR and 1H NMR were used to characterize the produced ligands and their associated Zn(II) complexes. The structure of Z1 was explored by single crystal X-ray diffraction analysis. The structural investigations of Z1 demonstrate that it exists in the form of a centrosymmetric dimer in which penta coordinated Zn(II) ions are inter connected via µ-phenoxo bridges from one of the phenolic oxygen atoms of each tetradentate Schiff base ligand to the opposite zinc(II) ions. The theoretical calculations, performed by DFT using the B3LYP/Def2-TZVP level of theory, directed that the intended outcomes are in compliance with the actual consequences. The nature and types of non-covalent interactions present among the sample molecules were also investigated by using QTAIM and NCI calculations. Furthermore, antimicrobial activities of the synthesized Schiff base ligands and their respective zinc(II) complexes were also examined against two Gram-positive (Staphylococcus aureus and Bacillus cereus) and two Gram-negative (Escherichia coli and Pseudomonas aeruginosa) bacteria, and two fungal species (Aspergillus brasiliensis and Candida albicans). The agar well diffusion method and poisoned media technique were used for the study of biological properties of bacterial and fungi species, respectively. According to assessments of inhibitory zones, metal chelates are found to be somewhat more efficient than free ligands. [ABSTRACT FROM AUTHOR]

A new potentially bidentate Schiff base ligand was synthesized from condensation reaction between ethylenediamine and 4-iodobenzaldehyde. The crystal structure of the compound was studied by single-crystal X-ray diffraction and it was shown that the compound was crystallized in monoclinic system with space group P21/n. In the crstal structure, the Schiff base molecule was located on special position with center of inversion in the middle of the C-C bond of the diamine segment. The intermolecular interaction energies of the interacting units were calculated by the theoretical calculations in the crystal structure. The theoretical calculations for interaction energies of the formed dimers from crystal structure were calculated by Gaussian program.

Deep‐ultraviolet nonlinear optical (DUV NLO) materials are attracting increasing attention because of their structural diversity and complexity. Using the two‐dimensional (2D) crystal structure prediction method combined with the first‐principles calculations, here we propose layered 18‐membered‐ring (18MR) boron oxide B2O3 polymorphs as high‐performance NLO materials. 18MR‐B2O3 with the AA and AB stackings are potential DUV NLO materials. The superior performing 18MR‐B2O3AB has an unprecedentedly high second harmonic generation coefficient of 1.63 pm V−1, the largest among the DUV NLO materials, three times larger than that of the advanced DUV NLO material KBe2BO3F2 and comparable to that of β‐BaB2O4. Its unusually large birefringence of 0.196 at 400 nm guarantees the phase‐matching wavelength λPM to reach this material's extreme absorption edge of ≈154 nm. [ABSTRACT FROM AUTHOR]

8-Hydroxyquinolin-5-sulfonic acid (8HQSA) was combined with 3-pyridineboronic acid (3PBA) or 4-pyridineboronic acid (4PBA) to give two zwitterionic monoboron complexes in crystalline form. The compounds were characterized by elemental analysis, single-crystal X-ray diffraction studies, and IR, 1H NMR, UV-Visible, and luminescence spectroscopy. The analyses revealed compounds with boron atoms adopting tetrahedral geometry. In the solid state, the molecular components are linked by charge-assisted (B)(O−H⋯−O(S) and N+−H⋯O(S) hydrogen bonds aside from C−H⋯O contacts and π⋯π interactions, as shown by Hirshfeld surface analyses and 2D fingerprint plots. The luminescence properties were characterized in terms of the emission behavior in solution and the solid state, showing emission in the bluish-green region in solution and large positive solvatofluorochromism, caused by intramolecular charge transfer. According to TD-DFT calculations at the M06-2X/6-31G(d) level of theory simulating an ethanol solvent environment, the emission properties are originated from π-π * and n-π * HOMO-LUMO transitions.

The synthesis and structural characterization of the monohydrated 1:2 cocrystal salt of acriflavine with 3,5‐dinitrobenzoic acid [systematic name: 3,6‐diamino‐10‐methylacridin‐10‐ium 3,5‐dinitrobenzoate–3,5‐dinitrobenzoic acid–water (1/1/1), C14H14N3+·C7H3N2O6−·C7H4N2O6·H2O] are reported. Single‐crystal X‐ray diffraction measurements show that the title solvated monohydrate salt crystalizes in the monoclinic space group P21 with one acriflavine cation, a 3,5‐dinitrobenzoate anion, a 3,5‐dinitrobenzoic acid molecule and a water molecule in the asymmetric unit. The neutral and anionic forms of 3,5‐dinitrobenzoic acid are linked via O—H...O hydrogen bonds to form a monoanionic dimer. Neighbouring monoanionic dimers of 3,5‐dinitrobenzoic acid are linked by nitro–nitro N—O...N and nitro–acid N—O...π intermolecular interactions to produce a porous organic framework. The acriflavine cations are linked with carboxylic acid molecules directly via amine–carboxy N—H...O, amine–nitro N—H...O and acriflavine–carboxy C—H...O hydrogen bonds, and carboxy–acriflavine C—O...π, nitro–acriflavine N—O...π and acriflavine–nitro π–π interactions, or through the water molecule by amino–water N—H...O and water–carboxy O—H...O hydrogen bonds, and are located in the voids of the porous organic framework. The intermolecular interactions were studied using the CrystalExplorer program to provide information about the interaction energies and the dispersion, electrostatic, polarization and repulsion contributions to the lattice energy. [ABSTRACT FROM AUTHOR]

Three novel multinuclear NiII complexes, namely, bis{μ‐2‐methoxy‐6‐[8‐(pyridin‐2‐yl)‐3,6‐dioxa‐2,7‐diazaocta‐1,7‐dien‐1‐yl]phenolato}bis[thiocyanatonickel(II)], [Ni2(L)2(NCS)2], 1, bis{μ‐2‐methoxy‐6‐[8‐(pyridin‐2‐yl)‐3,6‐dioxa‐2,7‐diazaocta‐1,7‐dien‐1‐yl]phenolato}bis[azidonickel(II)], [Ni2(L)2(N3)2], 2, and catena‐poly[[{2‐methoxy‐6‐[8‐(pyridin‐2‐yl)‐3,6‐dioxa‐2,7‐diazaocta‐1,7‐dien‐1‐yl]phenolato}nickel(II)]‐μ‐dicyanamidato], [Ni(L)(dca)]n, 3 {dca is dicyanamide, C2N3, and HL is 2‐methoxy‐6‐[8‐(pyridin‐2‐yl)‐3,6‐dioxa‐2,7‐diazaocta‐1,7‐dien‐1‐yl]phenol, C16H17N3O4}, with a half‐salamo‐based pyridine‐containing HL ligand have been synthesized and characterized by FT–IR, UV–Vis absorption spectroscopy, X‐ray crystallography, Hirshfeld surface analysis and density functional theory (DFT) calculations. The central NiII ions in complexes 1–3 are hosted in the half‐salamo‐based N3O‐donor cavity of the organic ligand. Complex 1 is a centrosymmetric dimer and two [Ni(L)(NCS)] units form a centrosymmetric dimeric structure, which is bridged by two phenolate O atoms. The two N atoms at the axial ends are provided by two NCS− ligands. In complex 1, each NiII ion has a six‐coordinated octahedral geometry. Complex 2 is similar to 1, but they differ in that the auxiliary NCS− ligand is replaced by N3−. However, complex 3 is a one‐dimensional coordination polymer constructed from [Ni(L)(dca)] units, which are connected by the auxiliary bidentate dca ligand viaN‐donor atoms. As with complexes 1 and 2, the NiII ion in 3 has a six‐coordinated octahedral geometry. [ABSTRACT FROM AUTHOR]

The single crystal of a silver complex bis (imidazole) silver(I) nitrate (Ag(C3H4N2)2(NO3), BISN) has been obtained and characterized by X‐ray single‐crystal diffraction. Its crystal thin film was prepared using direct growth on quartz substrates. The surface morphology of the thin film was studied by atomic force microscopy (AFM). The nonlinear optical (NLO) properties of the thin film were investigated by using closed‐aperture Z‐scan technique with 20 picosecond (ps) pulses at wavelength 532 nm. Using time‐dependent density‐functional theory (TDDFT) with the basis set LanL2DZ, its linear and NLO properties were calculated. [ABSTRACT FROM AUTHOR]

Two homologous new mixed‐metal phosphates K2PbBi2(PO4)2(P2O7) (I) and Rb2CdBi2(PO4)2(P2O7) (II) were successfully synthesized in A2BBi2(PO4)2(P2O7) (A = K, Rb, B = Pb, Cd) system through the traditional high‐temperature solid‐phase method. The single crystal structures of the two compounds are shown to be the unique three‐dimensional (3D) framework composed of different types of layers, but not isomorphic. We compared series compounds A2PbBi2(PO4)2(P2O7) (A = K, Rb, Cs), which are isomorphic and crystallize in the same space group Pnma. It is noteworthy that they are distinct different in degree of structural disorder, which is tuned by A‐site cations. The effect of A‐site cations is recognized by analyzing the disorder degree in three related structures and other available 182 mixed‐metal phosphates. To the best of our knowledge, such structural analysis is rarely reported in inorganic phosphates and the cation modulation strategy can be used to guide structural disorder according to the difference‐value (D‐value) of cation radii. Furthermore, the syntheses, thermal analysis, relevant spectroscopic measurements and theoretical calculations for I and II compounds were also discussed. [ABSTRACT FROM AUTHOR]

The solid-state chemistry of coordination complexes has become an actively developing research area of modern inorganic chemistry. Herein, Zn and Hg coordination compounds containing a N,N′-bidentate chelating Schiff-base ligand were synthesized and then characterized using spectroscopic techniques and single-crystal X-ray crystallography. The molecular structures and crystal packing modes of these complexes, as well as the crystal structures of related compounds, were investigated thoroughly using geometrical and Hirshfeld surface analyses, as well as theoretical calculations. It has been revealed that the supramolecular architecture of these series of coordination complexes is governed mainly by a combination of chelate···π and π···π stacking, and non-classical hydrogen bonding interactions. This study provides further insight into the understanding of the coordination chemistry of group IIB complexes containing Schiff-base ligand and the role of weak non-covalent interactions in the solid-state structure of coordination compounds. [ABSTRACT FROM AUTHOR]

The single crystals of a new coordination polymer catena‐poly[aqua‐dichlorido‐bis(1H‐imidazole)‐manganese(ii)] ([Mn(C3H4N2)2Cl2(H2O)]n) (CPADBIM) are obtained and characterized by X‐ray single crystal diffraction. It's second hyperpolarizability γ value is investigated by using a closed aperture Z‐scan technique with 20 ps pulses at wavelength 532 nm. Time‐dependent density‐functional theory with basis sets 6‐311++G(3d,3p) is used in computing the linear and non‐linear optical properties. The theoretical calculated γ value is in agreement with the experimental results. [ABSTRACT FROM AUTHOR]

Reaction between 2,4-dichlorophenylacrylic acid (HL) and triphenyltin (IV) hydroxide to yield the complex [(Ph3Sn)L]n (1). The complex has been characterized by elemental analysis, infrared spectrum and single crystal X-ray diffraction. The structural analysis shows that complex 1 possesses 1 D chain structure in which every tin atom is five coordinated. The 1 D chains linked by C(66)-H(66)·Cl(2) hydrogen bonds to aggregate in 2 D framework. Additionally, the PXRD, TG, and luminescent property were also investigated. The quantum chemistry calculations was performed with the Gaussian09 program. [ABSTRACT FROM AUTHOR]

The title compound, C30H44N2O4 [systematic name: 2,6-didecylpyrrolo[3,4-f]isoindole-1,3,5,7(2H,6H)-tetraone], consists of a central pyromellitic diimide moiety with terminal decyl groups at the N-atom positions. The centre of the molecule lies on a crystallographic inversion centre so the asymmetric unit contains one half-molecule. The molecule exhibits a rod-shaped conformation, like other similar compounds of this type, the distance between the ends of terminal decyl groups being 32.45 Å. The packing is dominated by a lamellar arrangement of the molecules, which is reinforced by C—H...O hydrogen bonds and C—O...π interactions, forming a classic herringbone structure. The molecular structure is consistent with the theoretical calculations performed by density functional theory (DFT).

Four new trinuclear hetero-metallic complexes, [(CuL) 2 (μ-X) 2 Cd] where X = Cl, Br, I and NO 3 have been synthesized using N 2 O 2 donor Schiff base ligand and structurally characterized. Non-covalent interactions (i.e. π···π, C H···O and Cu···Cu interactions) of the molecules have been characterized by means of high level DFT calculations. • Four new tri-nuclear copper(II)-cadmium(II) complexes have been synthesized. • All of the complexes have been structurally characterized. • Extensive non-covalent interactions have been observed in all of four complexes. • An exclusive C H···O interaction has been observed in crystal packing of complex 4. • These interactions have been investigated by high level DFT calculations. Four new tri-nuclear hetero-metallic copper(II)-cadmium(II) complexes [(CuL) 2 CdCl 2 ] (1), [(CuL) 2 CdBr 2 ] (2), [(CuL) 2 CdI 2 ] (3) and [(CuL) 2 Cd(NO 3) 2 ] (4) have been synthesized using [CuL] as "ligand complex" (where H 2 L = N,N′-bis(2-hydroxynaphthyl-methylidene)-1,3-propanediamine) and characterized by elemental analysis, IR, UV–Vis spectroscopy and single crystal X-ray diffraction studies. Crystal structure analyses reveal that all four complexes consist of a tri-nuclear moiety in which two square-pyramidal [CuL] units are bonded to a central Cd(II) ion through double phenoxido bridges. The Cd(II) is in a six-coordinate octahedral environment being bonded additionally to two mutually trans chloride (in 1), bromide (in 2), iodide (in 3) and oxygen atoms of nitrate (in 4) ions. Presence of several non-covalent interactions (i.e. π···π, C H···O and Cu···Cu interactions) has been observed in the crystal packing of all the four molecules that assist the formation of 1D supramolecular assemblies in the solid state. The interactions were investigated by means of high level DFT calculations (PBE0-D3/def2-TZVP) with the help of TURBOMOLE 7.0 program, characterized using Bader's theory of "atoms-in-molecules" (AIM) and rationalized using molecular electrostatic potential (MEP) surface calculations. [ABSTRACT FROM AUTHOR]

• The compound was characterized by LC/MS-TOF, IR, APT-NMR spectroscopies. • The crystal structure of the compound was determined by X-ray analysis. • FMO, MEP and Hirshfeld surface analysis for the compound were studied. • DFT/B3LYP and HF methods were used with the 6-31+G(d) basis set. • NLO properties were also investigated in this study. By condensation of 4‑methoxy benzaldehyde with (3‑chloro-2-methyl phenyl)-3-thiosemicarbazide a novel thiosemicarbazone derivative, N-(3‑chloro-2-methyl phenyl)-2-(4-methoxybenzylidene)hydrazine-1-carbothioamide (3), were synthesized and purified to describe the X-ray crystal structures. The structure of the synthesized thiosemicarbazone compound (3) was elucidated using FT-IR, 1H, APT-13C NMR, and mass spectroscopic methods. The geometry from X-ray experiment of the compound has been compared using the Hartree-Fock (HF) and density functional theory (DFT) with the 6-31G+(d) basis set. The obtained results show that the calculated results can well reproduce the structure of the compound. MEP, FMO, and Hirshfeld surface analysis were also performed for the structure. In addition, thermal analysis and non-linear optical (NLO) properties were also investigated in this study. [Display omitted] [ABSTRACT FROM AUTHOR]

The title compound, C15H18N2O2S {systematic name: 6-[2-(cyclohexylsulfanyl)ethyl]-5H-pyrrolo[3,4-b]pyridine-5,7(6H)-dione}, was obtained from the reaction of pyridine-2,3-dicarboxylic anhydride (synonym: quinolinic anhydride) with 2-(cyclohexylsulfanyl)ethylamine. The dihedral angle between the mean plane of the cyclohexyl ring and the quinolinic acid imide ring is 25.43 (11)°. In the crystal, each molecule forms two C—H...O hydrogen bonds and one weak C—O...π [O...ring centroid = 3.255 (2) Å] interaction with neighbouring molecules to generate a ladder structure along the b-axis direction. The ladders are linked by weak C—O...π [O...ring centroid = 3.330 (2) Å] interactions, resulting in sheets extending parallel to the ab plane. The molecular structure is broadly consistent with theoretical calculations performed by density functional theory (DFT).

Two new coordination polymers, namely [Zn2(phen)2(DHTA)]·2H2O (1) and [Zn2(PHDI)2(DHTA)]·2H2O (2) (phen = 1,10-Phenanthroline, PHDI = 1,10-Phenanthroline-5,6- dione, DHTA = 2,5-dihydroxyterephthalic acid) have been synthesized under hydrothermal conditions. The structures have been determined by single crystal X-ray diffraction, thermal gravimetric analysis, infrared spectrum and luminescent properties. The X-ray diffraction analysis revealed the coordination modes of Zn(II) centers from complexes (1) and (2) are different. In (1), there are unusual five coordinated and six coordinated Zn(II) ions. In (2), the center is four coordinated Zn (II). Through these coordination modes of Zn centers and the π-π stacking interactions of organic ligands, the two complexes are all connected to three-dimensional supramolecular networks. The solid-state photoluminescence properties of (1) and (2) have been investigated. The emission peaks are located at 538 and 603 nm, the emissions may be attributed to the metal-to-ligand charge-transfer. The quantum-chemical calculations have been performed on ‘molecular fragments’ extracted from the crystal structure using the B3LYP method in Gaussian 09. [ABSTRACT FROM AUTHOR]

Two noncentrosymmetric polyphosphates, namely LiCsP 2 O 6 and LiRbP 2 O 6 have been synthesized from the high temperature solution. The structural analysis suggests that both of them crystallize in orthorhombic space group Fdd 2 (No.43), with lattice parameters: a = 18.517(4) Å, b = 19.037(4) Å, c = 13.011(3) Å, and Z  = 32 for LiRbP 2 O 6, while a = 19.009(13) Å, b = 19.402(13) Å, c = 13.180(9) Å, and Z  = 32 for LiCsP 2 O 6 . In the structure, the PO 4 polyhedra are connected through corner-sharing to form 1D infinite (PO 3 ) ∞ chains stretching along the c axis, which are further linked by the LiO 4 polyhedra to construct a 3D framework with two types of tunnels. And the Rb/Cs atoms are filled in or around the periphery of the tunnels to keep the charge equilibrium. The IR spectra verify their structural validity. In addition, other characterizations including the UV−vis−NIR diffuse reflectance spectra, as well as first-principles theoretical studies have been performed on the two compounds. [ABSTRACT FROM AUTHOR]

High-resolution low-temperature X-ray diffraction experiments for doxycycline monohydrate and hydrochloride dihydrate have been performed. Translation-Libration-Screw (TLS) analysis for both crystal forms as well as the data from neutron diffraction experiment for hydrochloride combined with the Hansen-Coppens formalism resulted in precise charge density distribution models for both the zwitterionic monohydrate and a protonated hydrochloride crystal forms. Their detailed topological analysis suggested that the electron structure of doxycycline's amide moiety undergoes significant changes during protonation due to formation of a very strong resonance-assisted hydrogen bond. A notably increased participation of amide nitrogen atom and hydrogen-accepting oxygen atom in the resonance upon doxycycline protonation was observed. A comparison of TLS- and neutron data-derived hydrogen parameters confirmed the experimental neutron data to be vital for proper description of intra- and inter-molecular interactions in this compound. Finally, calculated lattice and interaction energies quantified repulsive Dox-Dox interactions in the protonated crystal form of the antibiotic, relating with a good solubility of doxycycline hydrochloride relative to its hydrate. [ABSTRACT FROM AUTHOR]

The new water-soluble derivative of pyrazino[2,3-f][1,10] phenanthroline has been synthesized and characterized by conductivity measurement, elemental analysis, FT-IR, 1 H NMR, 13 C NMR spectroscopic studies, as well as single crystal x-ray crystallography. Theoretical calculations have been performed using the density functional theory (DFT) in order to confirm the structure and understand the electronic structure of the synthesized compound. The DNA binding properties of the compound were investigated by absorption spectroscopy, melting temperature and viscosity measurements. The intrinsic binding constant, K b , was determined as 7.84 × 10 3  M −1  at 298 K. Thermodynamic parameters showed that the binding interaction is enthalpy-favored. All of the experimental results indicated that the binding mode of interaction between this compound and CT-DNA is groove binding. Furthermore, molecular modeling studies was done to confirm the binding mode. [ABSTRACT FROM AUTHOR]

The title compound 9,9′-(4,4′-(silinane-1,1-diyl)bis(4,1-phenylene))bis(9 H -carbazole) ( 6-bisCz ) has been designed and prepared to investigate its crystal structure and photophysical and electrochemical properties. 6-bisCz is crystallized in the centrosymmetric space group P −1. Interestingly, the asymmetric unit contains two molecules ( Z ′ = 2), and hence, the entire cell contains four units ( Z  = 4). The central silicon atom was arranged in pseudo-tetrahedral geometry defined by the two ipso -carbon atoms of the phenyl groups and two carbon atoms in the endocyclic hexyl ring, with average bond angles of 104.5(1)° and 108.5(1)°, respectively. UV/Vis absorption and photoluminescence spectra showed that the central silicon atom successfully disconnected electronic communication between the two peripheral phenylcarbazole units, yielding similar absorption and emission spectra to an unsubstituted carbazole monomer. The influence of the central silicon atom between the two phenylcarbazole units is also simulated by density functional theory calculations. Finally, electrochemical properties of 6-bisCz were investigated, and the analysis shows that an electropolymerized film was successfully formed during the electrochemical process. [ABSTRACT FROM AUTHOR]

According to literature data two structures of guanidine with nitrobenzoic acids are known. For guanidinium 4-nitrobenzoate the detailed studies of X-ray structure, vibrational and theoretical properties were performed. This compound was classified as second harmonic generator with efficiency of 3.3 times that KDP, standard crystal. On the contrary to mentioned above results for the guanidinium 3-nitrobenzoate the basic X-ray diffraction study was performed, only. On the basis of established crystallographic results, the detailed investigation of geometry and vibrational properties were made on the basis of theoretical calculation. According to this data the equilibrium geometry of investigated molecule was established. On the basis of this calculation the detailed computational studies of vibrational properties were performed. The theoretical IR and Raman frequencies, intensities and PED analysis are presented. Additionally, the NBO charges, HOMO and LUMO shapes and NLO properties of titled crystal were calculated. On the basis of these results the crystal was classified as second order generator in NLO but with bigger efficiency that guanidinium 4-nitorobenzoate compound. The obtained data are compared with experimental crystallographic and vibrational results for real crystal of guanidinium 3-nitrobenzoate. Additionally, the theoretical vibrational spectra are compared with literature calculations of guanidinium 4-nitrobenzoate compound. [ABSTRACT FROM AUTHOR]

A detailed structural and spectroscopic study of a new thiourea derivative 1-butyl-3-(1-naphthoyl)thiourea (1) is presented with the assistance of theoretical calculations. The X-ray diffraction structure analysis reveals a planar carbonylthiourea group, favoured by intra-molecular NH···O bond. The compound is arranged in the lattice as NH···O and NH···S bonded polymeric ribbons, that extend along the crystalb-axis. Molecular pairs involving N–H···S hydrogen bonds are a dominant contribution to packing stabilisation coming from coulombic component. Hirshfeld surfaces and two-dimensional-fingerprint plots show different intermolecular contacts and its relative contributions to total surface in each compound. The AIM approach shows the nature and strength of the strong and weak intramolecular interactions and the solvent effect, while NBO analysis reveals that the sulphur atom is responsible for the higher hyperconjugative stabilising energy. [ABSTRACT FROM PUBLISHER]

• The first salamo-type mixed-ligand metal(II) polymer was synthesized and characterized structurally. • The interaction forces existing within the polymer molecules were investigated by relevant theoretical calculations. • The antimicrobial activities of the two ligands and their polymer were investigated. In this work, a copper(II) coordination polymer [Cu 2 (L1)(L2)(NO 3)] n ·nCH 3 OH (Cu(II)-CP) with different structures of mixed salamo-type ligands was constructed for the first time. Single crystal X-ray diffraction analysis showed that the Cu(II)-CP asymmetric unit consists of two copper(II) atoms, fully deprotonated (L1)−, (L2)2− ligand units, one NO 3 − anion and one molecule of crystallized methanol. The two metallized ligand units are bridged by two oxygen atoms of NO 3 − to form unique mixed-ligand copper(II) coordination polymer. In addition, the six coordination atoms around the two Cu(II) atoms are all arranged in a distorted octahedral geometry. In the molecular structure of Cu(II)-CP , neighbouring molecules interact through intermolecular hydrogen bonds to form a two-dimensional supramolecular structure. Intermolecular interactions and molecular stability were further investigated by Hirshfeld surface analysis and other theoretical calculations. Finally, the antimicrobial activities of both ligands and Cu(II)-CP were investigated and found to exhibit excellent antibacterial activities. [Display omitted] A Cu(II) coordination polymer [Cu 2 (L1)(L2)(NO 3)] n ·nCH 3 OH with salamo-type mixed ligands was synthesized for the first time. The structure of the polymer was characterized and the intramolecular forces were studied through theoretical calculations. In addition, the antimicrobial activities of the two ligands and their polymer were investigated. [ABSTRACT FROM AUTHOR]

In this study, two dicationic asymmetrical diamine/copper(II) nitrate salt complexes of the general formula trans -[Cu II (NN′) 2 .H 2 O](NO 3 ) 2 were successfully synthesized using N , N -dimethylethylenediamine and N , N -diethylethylenediamine as asymmetrical diamine ligands. The structure of complex 2 was identified by X-ray single crystal diffraction analysis confirming that the bidentate ligand N , N -dimethylethylenediamine forms a penta-coordinated complex with an H 2 O molecule located around the copper(II) ion in a trans configuration. It was found that the metal centre is coordinated in a distorted square pyramidal fashion with a τ value of 0.274. The desired complexes were fully characterized using, MS, UV–Vis, CV, FTIR, TG/DTA, and Hirshfeld surface computational analysis. High level theoretical calculations were also performed in order to investigate the complexes structure, conformers, vibrational frequencies, and their excited states. [ABSTRACT FROM AUTHOR]

Single crystals of a new series of alkaline metal molybdates, LiNa 3 (MoO 4 ) 2 and LiAMo 3 O 10 (A = K + , Rb + , Cs + ), have been successfully synthesized through conventional high-temperature solid-state reactions. The compounds are structurally characterized by single-crystal X-ray diffraction and exhibit three-dimensional (3D) crystal structures consisting of 0D or 1D Mo O framework. Interestingly, when Mo O dimensionality changes from 0D of LiNa 3 (MoO 4 ) 2 to 1D of LiAMo 3 O 10 , the birefringence of LiAMo 3 O 10 is significantly enhanced to as large as BaTeMo 2 O 9 and Na 2 TeW 2 O 9 . The differences of bandgaps induced by anionic-group dimensionality are also discussed based on structural and theoretical analyses, which illuminate that the bandgap tends to be relatively broad for compounds with isolated MoO 4 tetrahedra in alkaline metal molybdate family. In addition, the dimensional reduction formalism was applied in the alkaline metal molybdate system to explore the changes of Mo O framework along with cation/Mo ratio for the first time. [ABSTRACT FROM AUTHOR]

A comparison of D-π-A + and D-A + cationic chromophores based on the quinolizinium system as new acceptor units is reported along with the results of studies into their linear and non-linear optical properties and electrochemical data. Experimental and theoretical data show that quinolizinium-based chromophores may provide a new generation of second-order non-linear materials with enhanced performance. The first hyperpolarizabilities were measured by Hyper-Rayleigh scattering experiments and the experimental data are supported by a theoretical analysis. In some chromophores the absence of a bridge (D-A + ) between the donor and acceptor fragments enhances the NLO properties and the single crystal structure of such a material has been determined by X-ray diffraction. [ABSTRACT FROM AUTHOR]

The synthesis and characterization by IR and 1 H NMR spectroscopy, ESI-TOF + mass spectrometry, cyclic voltammetry, single-crystal X-ray diffraction and thermal analysis of two novel heteroleptic Cu(I) complexes of general composition [Cu I (L1)(PPh 3 ) 2 ]PF 6 ·0.75CHCl 3 ( 1 ) and [Cu I (L2)(PPh 3 ) 2 ]PF 6 ·2.5CHCl 3 ( 2 ) PPh 3 = triphenylphosphine, L1 = cis -(±)-2-(2,5-di(pyridin-2-yl)-4,5-dihydro-1 H-imidazol-4-yl)pyridine and L2 = 2,4,6-tris(2-pyridyl)triazine) is reported. Both complexes show interesting photophysical properties, which were studied experimentally in solution and in the solid state by UV–Vis and fluorescence spectroscopy, and theoretically by using TD-DFT calculations. Additionally, their performance as co-sensitizer in DSSC was evaluated. [ABSTRACT FROM AUTHOR]

The title compound, C15H18N2O2S {systematic name: 6-[2-(cyclohexylsulfanyl)- ethyl]-5H-pyrrolo[3,4-b]pyridine-5,7(6H)-dione}, was obtained from the reaction of pyridine-2,3-dicarboxylic anhydride (synonym: quinolinic anhydride) with 2-(cyclohexylsulfanyl)ethylamine. The dihedral angle between the mean plane of the cyclohexyl ring and the quinolinic acid imide ring is 25.43 (11)º. In the crystal, each molecule forms two C--H... hydrogen bonds and one weak C--O ... [O ... ring centroid = 3.255 (2) Aº ] interaction with neighbouring molecules to generate a ladder structure along the b-axis direction. The ladders are linked by weak C--O ... [O ... ring centroid = 3.330 (2) Å ] interactions, resulting in sheets extending parallel to the ab plane. The molecular structure is broadly consistent with theoretical calculations performed by density functional theory (DFT). [ABSTRACT FROM AUTHOR]

A family of nonlinear optical materials that contain the halide, oxide, and oxyhalide polar units simultaneously in a single structure, namely ABi2(IO3)2F5 (A=K ( 1), Rb ( 2), and Cs ( 3)), have been designed and synthesized. They crystallize in the same polar space group ( P21) with a two-dimensional double-layered framework constructed by [BiF5]2− and [BiO2F4]5− units connected to each other by four F atoms, in which two [IO3]− groups are linked to [BiO2F4]5− unit on the same side. A hanging Bi−F bond of [BiF5]2− unit is located on the other side via ionic interaction with the layer-inserted alkali metal ions to form three-dimensional structure. The well-ordered alignments of these polar units lead to a very strong second-harmonic generation response of 12 ( 1), 9.5 ( 2), and 7.5 ( 3) times larger than that of potassium dihydrogen phosphate under 1064 nm laser radiation. All of them exhibited a wide energy bandgap over 3.75 eV, suggesting that they will have a high laser damage threshold. [ABSTRACT FROM AUTHOR]

The title compound, [Cu(Imz-H)(Imz)(N)] ( 1) (Imz-H = imidazole) was prepared by the reaction of CuCl·2HO with imidazole and sodium azide, and its structure was determined by X-ray crystallography. The crystal structure shows that the complex exists in the form of a two dimensional polymer consisting of dimeric [Cu(Imz-H)(Imz)(N)] and monomeric [Cu(Imz-H)(Imz)(N)] units. In the dimeric part each Cu(II) ion is bound to two nitrogen atoms of Imz-H or Imz and three nitrogen atoms of azide adopting a distorted square pyramidal geometry. In the monomeric part, the copper atom is disordered over two positions and is coordinated to two imidazole molecules (Imz-H), two bridging imidazolate (Imz-) groups, and two weakly bound azide ions. In order to validate the obtained structure, the structures of two complexes; [Cu(Imz-H)(Imz)(HN)(N)] containing one monomer and one dimeric unit as a model of 1 and a hypothetical complex, [Cu(Imz-H)(Imz)(HN)(N)] containing only dimeric units were fully optimized at the B3LYP-D3 level of theory. The interaction energy between the dimeric and monomeric units in the former complex was found to be almost twice larger that calculated between the dimeric units in the later complex. Therefore, the theoretical results support that the experimentally determined structure ( 1) is energetically more preferred than that containing only the dimeric units. The natural bond orbital (NBO) analysis of the model complexes of ( 1) was performed and the distribution of spin density at the atoms of [Cu(Imz-H)(Imz)(HN)(N)] and [Cu(Imz-H)(Imz)(HN)(N)] was discussed. The NBO charge on copper cation in the dimeric unit is 0.90 e and is smaller than that on the Cu(II) ion in the monomeric unit by 0.09 e. Antimicrobial properties of the complex were evaluated by minimum inhibitory concentration and the results showed that the complex exhibited no significant activities against the selected microorganisms. [ABSTRACT FROM AUTHOR]

A new strontium nitrate hydrate SrNO 3 (OH)·H 2 O has been synthesized by hydrothermal method. The title compound crystallizes in Pbca (no. 61) with the lattice parameters a = 9.801(5), b = 6.179(3), and c = 14.355(7) Å ( Z = 8). Isolated NO 3 anionic groups are combined through the SrO 9 polyhedra to form a three-dimensional (3D) network. From the aspect of cationic framework, the Sr O net can be simplified as an uninodal net with Schläfli symbol of {4 4 .6 6 } considering the SrO 9 polyhedra as five-connected (5c) nodes. Its UV–Vis–NIR diffuse reflectance spectral data indicate that it has a UV cut-off edge of 288 nm which corresponds to the energy gap of 4.31 eV. Theoretical calculations prove that SrNO 3 (OH)·H 2 O has a direct band gap of 3.72 eV, which is smaller than the experimental value. Crystal structural comparison among strontium nitrate hydrates indicates that different cation frameworks give anionic groups distinct restraint which has an influence on the arrangement of anionic groups. [ABSTRACT FROM AUTHOR]

The neutral radical (Me2-cAAC)2AlCl2 ( 2) is stabilized by cyclic (alkyl)(amino)carbenes (cAACs). Complex 2 was synthesized by reduction of the Me2-cAAC:→AlCl3 ( 1) adduct with KC8 in the presence of another equivalent of Me2-cAAC. The crystal structure of 2 shows that the Al−C bond lengths of the two carbenes bound to the Al center are considerably different, which is likely the result of intermolecular interactions. Quantum-chemical calculations from the gas phase give an equilibrium structure with identical Al−C bond lengths. Compound 2 exhibits monoradical character, which was confirmed by EPR measurements. A bonding analysis indicates that the unpaired electron resides mainly at the carbene carbon atoms. Compound 2 is an example for an unusual neutral Al radical. [ABSTRACT FROM AUTHOR]

• 4-(3-oxo-1,3-dihydroisobenzofuran-1-yl)aminobenzoic acid were prepared as a new ligand. • The crystal structure of new ligand and its metal complexes were characterized. • Antibacterial effects of these compounds were evaluated as in vitro and in silico. • The compounds were found to have significant antibacterial effect on K. pneumoniae. The current study outlines the syntheses of a new ligand 4-(3-oxo-1,3-dihydroisobenzofuran-1-yl)aminobenzoic acid (1) and its cobalt and nickel complexes [tetramethanolbis(4-(3-oxo-1,3-dihydroisobenzofuran-1-yl)aminobenzoato)cobalt(II) (2) and tetramethanolbis(4-(3-oxo-1,3-dihydroisobenzofuran-1-yl)aminobenzoato)nickel(II) (3). Their structures were established using FT-IR, elemental analysis, and UV–Vis, and also their molecular and crystal structures were clarified by single crystal X-ray diffraction technique. They belong to the monoclinic system P 2 1 / n (for 1) and C 2/ c (for 2 and 3) space groups with a = 12.2557 (5) Å, b = 5.8164 (3) Å, c = 17.7583 (6) Å, β = 94.202 (3)°, Z = 4 and V = 1262.48 (9) Å3 (for 1), a = 32.9005 (8) Å, b = 6.8552 (3) Å, c = 15.5507 (5) Å, β = 109.183 (3)°, Z = 4 and V = 3312.6 (2) Å3 (for 2) and a = 32.9604 (6) Å, b = 6.8265 (2) Å, c = 15.5949 (4) Å, β = 109.382 (3)°, Z = 4 and V = 3310.06 (14) Å3 (for 3). In the crystal structures of the ligand (1) and its complexes (2 and 3), the N–H···O, O–H···O, and C–H···O hydrogen bonds link the molecules, enclosing R 2 2(8), R 2 2(22) and R 2 2(26) ring motifs, into three-dimensional architectures. The weak C–H···π interaction (in 1) and the π...π interactions between the five-membered rings of the neighboring molecules with centroid to centroid distances of 3.8302 (10) Å (in 2) and 3.8441 (11) Å (in 3) further consolidate the crystal packings. Hirshfeld surface analyses further revealed the prevailing significance of π...π and H-bonding contacts. It indicates that the most important contributions for the crystal packings are from H...H (50.9%), H...O/O...H (22.8%), and H...C/C...H (14.7%) (for 2), and from H...H (50.9%), H...O/O...H (22.5%) and H...C/C...H (14.9%) (for 3). Hydrogen bonding and Van der Waals contacts are the dominant interactions in the crystal packings. Moreover, the optimized molecular structures, using density functional theory (DFT) at the B3LYP/6–311G(d,p) level, were compared with the experimentally determined ones. The HOMO–LUMO energy gaps were determined and the molecular electrostatic potential (MEP) surfaces were calculated at the B3LYP/6–31 G level to predict sites for electrophilic and nucleophilic attacks. The antibacterial effects of the synthesized compounds on B. subtillis and S. aureus, K. pneumoniae, and P. multocida were investigated using the agar well diffusion method. According to the results obtained, the inhibitory properties of these compounds, which were found to have significant effects on K. pneumoniae in vitro conditions, were also investigated in silico with the help of Molecular Docking studies. The compounds were found to have a significant antibacterial effect on K. pneumoniae bacteria. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • The growth of 1 and 2 results from the equilibrium between the chelidamic acid anions. • In 2 , the H 2 cda− anion as a counterion exists in a unique keto tautomeric form. • The formation of 3D networks is realized by hydrogen bonds and π⋯π stacking interactions. • The presence of chel acid tautomers is explained by DFT calculated relative energies. Two copper(II) chelidamate compounds with 2,2'-bipyridine were obtained as crystals [Cu(Hcda)(bpy)(H 2 O)]∙2H 2 O (1) and [Cu(H 2 cda)(bpy)(H 2 O)](H 2 cda) (2) (H 3 L = H 3 cda = chel = chelidamic acid, bpy = 2,2′-bipyridine) through one-pot synthesis. In 1 , the tridentate Hcda2− ligand, an enol tautomer of the 4-hydroxypyridine type, and a bpy molecule coordinate the Cu(II). In 2 , the same tautomer of the tridentate H 2 cda− ligand (with one deprotonated carboxylic acid), along with bpy, forms a cationic [Cu(H 2 cda)(bpy)(H 2 O)]+ complex. It is charge-balanced by an H 2 chel− anion, featuring the rare keto tautomer of the 4-pyridone type. The alternately protonated and deprotonated carboxylic groups of both tautomers are involved in hydrogen bonds leading to 1D chains. The adjacent chains are connected to form 2D chain by hydrogen bonds between two different tautomers of chel. As confirmed by the DFT calculations, the crystal structures of 1 and 2 are mainly stabilised by hydrogen bonds and electrostatic interactions, the latter being especially noticeable in the [Cu(H 2 cda)(bpy)(H 2 O)]+ cationic complex (2). Additionally, π⋯π stack is formed between aromatic ring fragments. The presence of each particular tautomer in the crystal structures of 1 and 2 can be explained by the relative energies of the respective structural moieties in the aqueous environment, combined with coordination and intermolecular interaction preferences. [ABSTRACT FROM AUTHOR]

Type-I clathrates of Rb 6 Na 2 Ge 44.89(1) , Cs 6 Na 2 Zn 4 Ge 42 and Cs 6.40(1) Na 1.60(1) Ga 8 Ge 38 were synthesized via solid-state reaction. Rb 6 Na 2 Ge 44.89(1) , Cs 6 Na 2 Zn 4 Ge 42 and Cs 6.40(1) Na 1.60(1) Ga 8 Ge 38 were found to crystalize in the cubic space group of Pm 3 ̅ n with lattice parameters of a =10.72755(5) Å, a =10.79501(8) Å and a =10.79726(5) Å, respectively. Theoretical calculations indicated semiconducting features for the calculation models of Rb 6 Na 2 Ge 44 , Cs 6 Na 2 Zn 4 Ge 42 and Cs 6 Na 2 Ga 8 Ge 38 with band gaps of 0.002 eV, 0.297 eV and 0.221 eV, respectively. [ABSTRACT FROM AUTHOR]

The title compound (Z)-5-(4-chlorobenzylidene)-3-(2-ethoxyphenyl)-2-thioxothiazolidin-4-one (CBBTZ) was characterized by X-ray single crystal diffraction, 1H NMR and 13C NMR spectra. Theoretical investigations were carried out using HF and DFT levels of theory at 6-31G(d,p) basis set. The X-ray structure is compared with that computed. The calculated geometrical parameters are in good agreement with those determined by X-ray diffraction. The dihedral angle between the two benzene rings is 16.89(5)° indicating that the structure is non planar. The molecule exhibits intraand intermolecular contacts of type C–H···O, C–H···S and C–H···Cl. The intercontacts in the crystal structure are explored using Hirshfeld surfaces analysis method. [ABSTRACT FROM AUTHOR]

The compounds [Ni(behdtc)2] (1) and [Ni(behdtc)(NCS)(PPh3)] (2) (where behdtc = bis(2-ethylhexyl)dithiocarbamate) were synthesized and characterized by elemental analyses, electronic, IR, and NMR (1H and13C) spectroscopy. UV-vis spectral data are consistent with the formation of square-planar nickel complexes. The N13CS2carbon signal for [Ni(behdtc)(NCS)(PPh3)] is observed at 204.4 ppm with an upfield shift of about 3.8 ppm compared with that found in [Ni(behdtc)2] (208.2 ppm). The observed shielding in [Ni(behdtc)(NCS)(PPh3)] indicates the effect of PPh3on the mesomeric drift of electron density toward nickel through the thioureide C-N bond. This observation is supported by the higher νC-N values observed in the IR spectrum of the complex2. A single crystal X-ray analysis of complex 2 proved four coordinated nickel in a distorted square-planar arrangement with a S2NP donor set. A significant asymmetry in the Ni–S bond in 2 (2.1690(10) and 2.2234(10)Å) supports the less effective trans effect of SCN−over PPh3. Molecular electrostatic potential surface map shows that there are no possible sites for nucleophilic attack and S atom of thiocyanate is preferred possible site for electrophilic attack. [ABSTRACT FROM AUTHOR]

A silver(I) complex containing cyanide and diazinane-2-thione (Diaz) ligands, [Ag(Diaz) 2 Ag(CN) 2 ] ( 1 ) was prepared and its crystal structure was determined. The compound crystallizes in the orthorhombic space group, Pnma . The structure of the complex consists of [Ag(Diaz) 2 ] + cationic and [Ag(CN) 2 ] − anionic units, which are associated through Ag NC and argentophilic interactions to form a two dimensional polymeric network. An upfield shift in the C S resonance of Diaz in 13 C NMR and downfield shift in N H resonance in 1 H NMR are consistent with sulfur coordination to silver(I). The appearance of a band around 2100 cm −1 in IR and a resonance at 143 ppm in 13 C NMR indicates the binding of cyanide to silver(I). DFT calculations on model head-to-tail dimeric systems mimic the bridging behavior of the [Ag(CN) 2 ] − anionic units that connect the metal center of the cationic unit by N→Ag coordination in one N terminus, whereas the other terminal N atom is involved in hydrogen bonding towards Diaz H atoms. [ABSTRACT FROM AUTHOR]

New derivatives of chrysin containing 2-mercaptopyridine ( 2a – 2e ) or 5-(trifluoromethyl)-2-mercaptopyridine ( 3a – 3e ) moieties were prepared from the reaction between bromides ( 1a – 1e ) and 2-mercaptopyridine or 5-(trifluoromethyl)-2-mercaptopyridine, respectively. Their structures were elucidated by NMR, IR and elemental analysis. The molecular structure of compounds 1a, 1c – 1e , 2b – 2e and 3a was determined by single-crystal X-ray diffraction studies. All rings in these structures are nearly coplanar and they showed an intramolecular hydrogen bond between the phenolic hydroxyl H atom and the carbonyl O atom that forms a six membered ring. The crystal packing also showed a wide variety of intermolecular contacts such as C–H⋯A, π–π, C–H⋯π and lone pair⋯π interactions which were supported by quantum theory of atoms in molecules (QTAIM), Hirshfeld surface, and fingerprint plot analyses. Biological activity of all compounds was tested in growth assays of the nematode Caenorhabiditis elegans . Compounds 2e , 3b and 3c inhibited larval development. [ABSTRACT FROM AUTHOR]

The intermolecular charge transfer CT-complexes of tris(2-aminoethyl)amine (TREN) with different π-acceptors such as picric acid (PIC), o-chloranil (CHL) and tetracyanoquinolines (TCNQ) were investigated in both solid and liquid phase. Spectroscopic techniques, such as FT-IR, 1 H NMR, 13 C NMR, and UV–vis, were used to characterize the molecular complexes. Spectral data, for example, formation constants, molar extinction coefficient, standard free energy, and ionization potentials for the complexes were calculated for the 1:1 molecular CT-complexes. Exploring the single crystal of TREN/PIC, grown by slow evaporation technique from methanol solution at room temperature, shows that CT-complex stabilized by two noncovalent interactions, namely, hydrogen bond and dipole–dipole interactions. In addition, the structure of tris(2-aminoethyl)amine and CHL and TCNQ complexes were investigated by DFT calculations at B3LYP/6-311 ++G(d,p) level of theory. [ABSTRACT FROM AUTHOR]