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Single crystals of a new acentric barium iodide-thiocyanate tetrahydrate Ba(SCN)I·4H2O (1) are prepared by the isothermal evaporation of aqueous solutions containing Ba(SCN)2·3H2O and BaI2·2H2O in the 1:1 molar ratio. The crystal structure of 1 is determined by XRD. The substance crystallizes in the orthorhombic unit cell, the I2mb space group, a = 7.4803(2) Å, b = 16.0959(4) Å, c = 24.0037(5) Å. The crystal motif is pseudo-layered and is formed by a packing of two types of layers, cationic and anionic ones, parallel to (010). The cationic layer is composed of distorted [BaS2N2(H2O)6] face-sharing 10-vertex polyhedra forming zigzag chains along the [100] axis. The neighboring chains are combined into a layer through common vertices corresponding to sulfur atoms. The anionic layer is formed by iodine atoms combined with the cationic layer into a 3D framework by O–H⋯I hydrogen bonds. [ABSTRACT FROM AUTHOR]

We discuss the methodological questions of measuring unit cell parameters of small crystals in Bond's scheme on a commercial diffractometer equipped with a three-circle goniometer and a 2D detector. The effect of the sample eccentricity on the positions of X-ray diffraction reflections during rotation about φ and ω axes is examined. The approach is developed to eliminate the effect of the sample eccentricity related to rotation about the φ axis by positioning one of the crystallographic directions along the ω axis. The unit cell parameters are measured for the reference Si and Ge single crystals used in this work with relative error Δa/a no worse than 6.5·10–5. [ABSTRACT FROM AUTHOR]

A fine crystalline sample of the cubic modification (space group , Z = 16) of gadolinium oxide (C-Gd2O3) is grown by the solution–melt technique. The single crystal X-ray diffraction analysis performed at 150 K and 298 K reveals a relative increase in the unit cell parameter by 0.08%. The parameter at 300 K is refined by two independent procedures: in Bond's scheme (a = 10.8152(9) Å, relative error Δa/a = 8·10–5) and by calibrating the equatorial circumference according to the external reference (a = 10.8145(6) Å, relative error Δa/a = 5.1·10–5). The values obtained coincide within the experimental error with data for the polycrystalline reference described by the National Bureau of Standards of the United States. The dependence a(T) is studied in the range of 90-490 K with a step of 10 K. Experimental points are described by second degree polynomial a = 10.801 + 2.7·10–5T + 6.0·10–8T2. [ABSTRACT FROM AUTHOR]

A series of 5-(2,4-dichlorophenyl)-1,3,4-oxadiazole-2-thione alkyl derivatives are obtained. Structures of the products are determined from the IR, UV, 1H and 13C NMR spectroscopic results together with single crystal X-ray diffraction (XRD). The aromaticity of the 1,3,4-oxadiazole ring is estimated by single crystal XRD and DFT calculations using the Multiwfn program package. It is found that in S-derivatives, the π electron system is redistributed in the pseudo-aromatic 1,3,4-oxadiazole-2-thione moiety relative to initial 5-(2,4-dichlorophenyl)-1,3,4-oxadiazole-2(3H)-thione. In the S-derivatives of 5-(2,4-dichlorophenyl)-1,3,4-oxadiazole-2-thione the aromaticity of the 1,3,4-oxadiazole heterocycle is lower than that in N3-derivatives. [ABSTRACT FROM AUTHOR]

New complexes of magnesium with asymmetric fluorinated β-diketones are synthesized: pentafluoropropionyl (Hpfpac, 6,6,6,5,5-pentafluorohexane-2,4-dione) and heptafluorobutyrylacetone (Hhfbac, 7,7,7,6,6,5,5-heptafluoroheptane-2,4-dione). The [Mg(H2O)(EtOH)(pfpac)2] 1 and [Mg(H2O)2(hfbac)2]·H2O 2 phases are characterized by a number of methods. The structures of crystals of 1, 2, and [Mg(EtOH)2(hfbac)2] 3 are determined by the single crystal X-ray diffraction analysis. Magnesium atoms have a distorted octahedral environment, and neutral ligands are in the trans-position. Molecules are involved in systems of OH⋯Odik hydrogen bonds, forming layers (2) or chains (1, 3). A relative evaluation shows that 2 is more volatile than 1. Structures of molecules and packing characters are compared with those of a series of related β-diketonate complexes. The effect of an increase in the ligand perfluoroalkyl chain (L = tfac, trifluoroacetylacetonate ion), including isoformular [Mg(H2O)2(L)2]·H2O, is shown. [ABSTRACT FROM AUTHOR]

In order to develop the application of 1,3,4-oxadiazole compounds in the direction of fluorescent probes, we modified the probes by introducing 2-(bromomethyl)pyridine on the amino group of 1,3,4-oxadiazole derivatives, and synthesized HL1(2-(5-(2-aminophenyl)-1,3,4-oxadiazol-2-yl)-N-(pyridin-2-ylmethyl)aniline). Its structure was characterized by NMR, HRMS and single crystal X-ray diffraction. The weak interaction of HL1 was analyzed by using Multiwfn to draw Hirshfeld surface. The HOMO and LUMO orbitals of HL1 were analyzed in B3LYP/6-311++G basis set using DFT theory. HL1 is highly selective to Sn4+ in ACN, LOD = 5.08∙10–7 M, Ka = 1.73∙103M–1. [ABSTRACT FROM AUTHOR]

Single crystals of hexahydrates of divalent fluoridotitanates MTiF6·6H2O (M = Mn, Co, Ni, Zn) are synthesized. Their crystal structures are determined by X-ray diffraction at room temperature (RT-structure) and below the phase transition (LT structure). The phase transition is accompanied by a transformation of the disordered trigonal lattice into the ordered monoclinic one. The initial RT-structures differ in the set and strength of O–H⋯F hydrogen bonds linking isolated [M(H2O)6]2+ and [TiF6]2– octahedra into a 3D framework. There is a correlation between the strength of hydrogen bonds and the thermal behavior of the complexes. [ABSTRACT FROM AUTHOR]

Five new metal-organic frameworks based on 4,8-disulfo-2,6-naphthalenedicarboxylic acid (H4dsndc) are obtained: [Cd2(dsndc)(dmf)6] (1), [Mn2(dsndc)(dmf)6] (2), [Zn2(dsndc)(dmf)6] (3), [Co2(dsndc)(dmf)6] (4), and [Cd2(dsndc)(dma)6] (5) (DMF = N,N-dimethylformamide, DMA = N,N-dimethylacetamide). The four of them (1–4) are isostructural layered coordination polymers. The structures of all compounds are determined by the single crystal X-ray diffraction analysis. Compounds 1–3 and 5 are obtained as chemically and phase-pure and are characterized by the standard complex of physicochemical techniques (powder XRD, IR, TGA, and CHN). Photoluminescence excitation and emission spectra are recorded for compound 3, and a quantum yield of 18% is obtained. [ABSTRACT FROM AUTHOR]

7-Bromo-5-(tert-butyl)-2-phenyl-1H-indene (1) and 6,7-dibromo-2,4-dimethyl-2,3-dihydro-1H-inden-1-one (2) are analyzed by single crystal X-ray diffraction. The conformational structure, vibrational spectrum of molecules, topology and hierarchical complexity of crystal structures are discussed. The structure of 1 is layered and contains (100) molecular layers of the tts topological type. The structure of 2 does not contain long molecular ensembles but demonstrates short Br⋯O contacts linking molecules into a centrosymmetric dimer. [ABSTRACT FROM AUTHOR]

Two new complexes of nickel(II) benzoylhydrazone 2-(N-tosylamino)benzaldehyde (H2L) with additional heterocyclic donor ligands L1 = 2,2′-bipyridine and L2 = 1,10-phenanthroline are synthesized. Structures and compositions of the obtained compounds are determined by elemental analysis, 1H NMR, and IR techniques. Crystal and molecular structures of the Ni(II) complexes are determined by single crystal X-ray diffraction. The adducts are shown to have dimeric structures: Ni2L2L1(CH3OH) and Ni2L2L2(CH3OH). In both adducts, one of nickel(II) ions is in a distorted square-planar environment while another is in the octahedral environment due to additional coordination of 2,2′-bipyridine or 1,10-phenanthroline and a methanol molecule. The biological activity of the complexes is studied. It is found that both adducts exhibit the protistocidal activity against Colpoda steinii, with Ni2L2L1(CH3OH) being twice less active and Ni2L2L2(CH3OH) being twice more active than the chloroquine reference. [ABSTRACT FROM AUTHOR]

An original procedure is proposed to refine unit cell parameters (UCPs) of single crystals in Bond's scheme. The procedure involves the use of a modern laboratory diffractometer equipped with a 2D detector and a three-circle goniometer. At the first stage, preliminary UCPs, diffraction class, and crystal orientation relative to goniometer axes are determined. Then φ and ω angles are calculated to bring an appropriate (occurrence of a well-resolved doublet, intensity) reflection hkl on the equatorial plane. The measurement in Bond's scheme is carried out at two symmetric positions of the detector ±2θD ≈ 2θhkl. The principal difference from the measurement on a single crystal spectrometer consists in refusing to plot the reflection profile I(ω) and passing to ω-scans with a width of 3-4°, which allows the measurement of the Kα1/Kα2 doublet profile. After its processing by two independent 2D functions, coordinates of the maxima are determined, and then the 4θhkl. Angle is found based on angular sizes of the detector pixel and the difference in the coordinates of X Kα1-component reflections obtained in symmetric positions. In this approach, measurement errors are related to the accuracy of placing the detector in two symmetric positions and the correctness of processing 2D reflection profiles. In the study of reference Si and Ge single crystals in the range of 2θD angles close to 100°, UCP deviations from the theoretical values are found to not exceed 0.0004 Å, and the relative measurement accuracy is 6·10–5. The refinement of UCPs of single crystals grown in the Y2O3–Eu2O3 system by the melt-solution technique indicates the formation of the (Y1–xEux)2O3 solid solution with the x value range of 0.27-0.40. A scheme is proposed to improve the measurement accuracy when the procedure is transferred to the diffractometer with synchrotron radiation. [ABSTRACT FROM AUTHOR]

By the condensation of 4-amino-5-R-2,4-dihydro-3H-1,2,4-triazole-3-thiones with anthracene-9- carbaldehyde, respective 4-[(anthracene-9′-ylmethylene)amine)]-5-R-2,4-dihydro-3H-1,2,4-triazole-3-thiones are prepared and structurally characterized by NMR, UV, IR spectroscopies, high-resolution mass spectrometry, and single crystal XRD. The effect of a substituent at position 5 in triazole moieties of azomethines obtained on their head-to-head or head-to-tail crystal packings is determined. [ABSTRACT FROM AUTHOR]

The molecular structure of 3-cyano-4-amino-1,2,5-oxadiazole-2-oxide (3-cyano-4-aminofuroxan, CAFO) in the gas phase is studied for the first time by gas-phase electron diffraction (GED) and quantum chemical calculations, and the equilibrium parameters of this molecule are determined. The data obtained are compared with those of related compounds analyzed by GED and single crystal X-ray diffraction. It is shown that the best agreement with the experiment is obtained at the B3LYP/aug-cc-pVTZ level of theory. The information on the molecular structure of free CAFO will be useful for the structural studies of compounds containing furoxan moieties. [ABSTRACT FROM AUTHOR]

First example of a Zr(IV) complex with an aromatic carboxyamidate ligand, Zr(mba)4 (mba = N-methoxybenzamidate), is prepared. Its structures in the solution (1H, 13C{1H} NMR) and in the crystal phase (single-crystal XRD) are determined and compared with those of the initial N-methoxybenzamide Hmba. During the complexation, mba– ligands exhibit a bidentate cyclic function through oxygen atoms. The coordination polyhedron of the metal atom is a distorted square antiprism, the lengths of Zr–O bonds with carbonyl and methoxy groups fall within 2.08-2.09 Å and 2.29-2.33 Å, respectively. Despite the presence of available phenyl rings, the Zr(mba)4 and Hmba crystals contain no intermolecular π–π-interactions, but exhibit C–H⋯π and N–H⋯O contacts, respectively. According to the DSC data, Hmba undergoes no phase transitions from 130 K up to the melting point (335.0±0.5 K, ΔH = 15.1±0.1 kJ/mol, ΔS = 45.2±0.2 J/(mol·K)), while Zr(mba)4 exhibits a reversible solid-phase transition (Tonset = 177.4±0.5 K, ΔH = 0.68±0.20 kJ/mol, ΔS = 3.8±0.1 J/(mol·K)). Studying the Zr(mba)4 crystals at 150 K and 200 K shows that this transition is not accompanied by the crystal deformation and is apparently caused by the rotation of phenyl groups. Due to this conversation, the space group changes from P21/c to P21/n, and one of the unit cell parameters increases by 3 times. [ABSTRACT FROM AUTHOR]

Neutral complex [L2CoCl2] is obtained by the reaction of cobalt(II) chloride with E-(((4-iodophenyl)imino)methyl)phenol (L), and its structure is studied by single crystal X-ray diffraction. The structure contains I⋯Cl halogen bonds whose energies are estimated by quantum chemical calculations. [ABSTRACT FROM AUTHOR]

A new method is proposed to synthesize ethylenediamine complex [RuNO(en)2OH]I2 from K2[RuNOCl5], which increases the target product yield to 76%. Subsequent treatment of nitrate salt [RuNO(en)2 OH](NO3)2 with concentrated HF with the precipitation of HClO4 gives [RuNO(en)2F](ClO4)2 with a quantitative yield. According to the single crystal XRD data, in the [RuNO(en)2F]2+ cationic moiety, nitrosyl and fluoride are in the trans-position relative to each other, and in the ruthenium coordination environment, the equatorial plane is composed of four nitrogen atoms from ethylenediamine ligands. The 450 nm light irradiation of the [RuNO(en)2F](ClO4)2 complex at 80 K results in the formation of metastable linkage isomer MS1 with nitrosyl group coordination through the oxygen atom. According to the IR spectroscopic data, the population of MS1 is about 1%, and the respective vibrational band disappears when heated in a temperature range of 280-310 K. The activation parameters of the MS1–GS (ground state) transition according to the DSC data are Ea = 107.1±6.8 kJ/mol, lnk0 = 36.1±2.6. [ABSTRACT FROM AUTHOR]

Single crystals of Fe(dpm)3 (dpm - dipivaloylmethanate) are analyzed by X-ray diffraction in the temperature range of 90-365 K. A new crystal modification is found in the range of 90-100 K (space group , Z = 8); a phase transition is confirmed to occur at 230 K (space group , Z = 4). In the range of 250-365 K, a relative increase in the monoclinic unit cell parameters (space group C2/c, Z = 8) is Δa/a = 0.67%, Δb/b = 1.16%, and Δc/c = 0.47%; β angle decreases by 3.3%. In the range of 90-365 K, a relative increase in the molecular volume is 6.65%, with average Fe–O distances and chelate angles ∠O–Fe–O being almost unchanged. Hirshfeld surfaces are constructed for the structures at 90 K, 130 K, 250 K, and 365 K. The Fe(dpm)3 layers obtained by physical vapor deposition (PVD) and crystallization during spin coating on different inorganic substrates are studied, orientation is determined, and structural features are analyzed in [1 0 0] and [0 0 1] directions. [ABSTRACT FROM AUTHOR]

An efficient green method is developed as a one-pot synthesis of pyrrolo[1,2-c]imidazole-1-one derivatives under microwave conditions via two components in a substoichiometric quantity of water. The conformational and structural studies are conducted through DFT optimization and single crystal X-ray diffraction. The molecular packing is mediated through hydrogen bonding and C–H⋯π interactions. The Hirshfeld surface analysis highlights significant H–H interactions in all compounds, with compound 2a exhibiting the highest percentage. HOMO and LUMO studies reveal compound 2a as more stable and less reactive. The molecular electrostatic potential provides the charged proportionality along with the molecular surface. The drug-likeness properties suggest that compounds 2b, 2c, 2d, 2e, 2f, 2g, and 2i possess favorable properties for potential pharmaceutical applications. [ABSTRACT FROM AUTHOR]

A new cocrystal solvate possessing 2,7,14-trihydroxytriptycene (THT) and 4,4′-bipyridine (bpy) is grown from a MeOH solution by solvent evaporation to form THT·0.5bpy·MeOH·H2O (1). The crystal structure of 1 is determined by single crystal X-ray diffraction in the monoclinic space group C2/c. In new cocrystal solvate 1, the asymmetric unit consists of one unit of THT, a half unit of disordered bpy, one unit of a water molecule, and one MeOH molecule. A 2D supramolecular architecture is observed in 1, which links THT, bpy and solvent water molecules via classical O–H⋯N and O–H⋯O hydrogen bonds. The MeOH and water molecules entrapped in 1 form stabilizing hydrogen bonds with the surrounding "trimeric cocrystals". Furthermore, we investigate whether these hydrogen bonds stabilize the crystal packing or not. The calculations are carried out using Hydrogen Bond Statistics and Full Interaction Maps packages, and the results exhibit the common bonding behaviour in terms of bond distances and strength. [ABSTRACT FROM AUTHOR]

The Mn2+-doped optical quality Li2–2xMg2+x(MoO4)3 single crystals were grown by the low-thermal-gradient Czochralski method. Photoluminescence (PL) and photoluminescence excitation (PLE) spectra for investigated crystals were studied at 77 K and 300 K. Green and red emission bands of Mn2+ are interpreted in terms of different structural positions that occupied by impurity manganese ions in Li2–2xMg2+x(MoO4)3. Absorption investigations show the characteristic Mn2+ absorption features, namely a sharp absorption peak at 410 nm. CIE investigation results show that Mn2+-doped Li2–2xMg2+x(MoO4)3 single crystals are prospective materials in pcWLED due to from green to red emission bands in PL spectrum. Correlated color temperatures (CCT) and color purity (CP) of investigated crystals were calculated. [ABSTRACT FROM AUTHOR]

The aza-macrocyclic ligand Py3Am based on a pyridine-azacrown compound containing three chelating acetamide groups is synthesized for the first time. Its complexes with nickel and zinc are characterized by NMR, mass, and IR spectroscopic techniques, and their crystal structures are determined by the single crystal X-ray diffraction analysis. In both complexes, the transition metal atom is completely encapsulated into the macrocycle cavity with the formation of a similar coordination environment. The presence of an additional outer-sphere Na+ cation in the structure of the zinc complex weakly affects the conformation of the complex. Despite that the geometric parameters indicate that the ligand is not ideal for the coordination of small cations of transition metals, a combination of these types of donor groups provides the efficient coordination of the ligand, which is important for the stability of complexes in a biological medium. [ABSTRACT FROM AUTHOR]

New silanediamide complexes of rare-earth elements are synthesized: [{Dy(Me2Si(NMes)2)(THF)2}2(μ-Cl)2] (Dy1), [{Ln(Me2Si(NMes)2)(THF)2}2(μ-BH4)2] (Ln2, Ln = Y, Dy), and [{Ln(Me2Si(NMes)2)(THF)2}2 (μ-SPh)2] (Ln3, Ln = Y, Tb, Dy), Mes = 2,4,6-(CH3)C6H2=mesityl. The compounds are isolated as crystalline phases Dy1, Ln2 (Ln = Y, Dy), Y3·2THF, Tb3·2C7H8, Dy3·2THF, and Dy3·2C7H8 and characterized by single crystal X-ray diffraction. All complexes have a binuclear structure; a silanediamide ligand is chelated to each Ln atom, and Cl–, , or SPh– act as bridges. By photoluminescence spectroscopy of the solutions of Tb and Dy complexes in THF it is shown that (Me2Si(NMes)2)2– is an effective ligand antenna, which sensitizes metal-centered emission of these lanthanides. [ABSTRACT FROM AUTHOR]

Deprotonation of SiMe2(HNPbt)2 proligand (1) by Li(NTms2) (Tms = SiMe3) base results in the formation of SiMe2(LiNPbt)2 (Pbt = 2-(1,3-benzothiazol-2-yl)phenyl) in solution, which further reacts with GdCl3 yielding [Li(THF)4][Gd(SiMe2(NPbt)2)2] complex (2). In an attempt to obtain 2 with the use of n-butyllithium as a base, an unexpected product with an intricate structure - [Gd{Me2Si(NPbt)(o-NC6H4-C(Bu)2(o-NHC6H4S))}(μ-NHPbt)Li(THF)] complex (3) is isolated and structurally characterized. The thiazole ring of one of the substituents of the silandiamide ligand is open in it, while two butyl groups are attached to the thiazole C2 carbon atom. In the reaction of 1 with an excess of butyllithium and YCl3, a product with the ligand also containing the C(Bu)2 moiety is formed, which is shown by 1H NMR. Apart from it, double complex salt [Li(THF)4][Y(SiMe2(NPbt)2)2] (4) crystallized as a solvate with Et2O is isolated from the reaction mixture. In an attempt to obtain a monosubstituted [Y(SiMe2(NPbt))Cl] complex, compound 4·2THF forms along with several crystals of [{Y(SiMe2(NPbt)2)}2(μ-OBu)2] complex (5) the structure of which is characterized by single crystal X-ray diffraction. The photophysical properties of compound 2 are studied in the THF solution and in the crystalline state. [ABSTRACT FROM AUTHOR]

The structural characterization of 3,4-dichloroisothiazole-5-carboxylic acid is performed for the first time along with the preparation of the first coordination compound based on it - a mixed-ligand europium(III) complex with 3,4-dichloroisothiazole-5-carboxylic acid and 1,10-phenanthroline. The coordination compound is characterized by the elemental analysis, single crystal and powder X-ray diffraction (XRD), and IR spectroscopy. According to the single crystal XRD data, the obtained complex is a binuclear compound with the formula [Eu2L6(phen)2(H2O)2]·6H2O. Its structure corresponds to the Chinese lantern type. The isothiazole derivative exhibits both monodentate and bidentate-bridging coordinations binding europium ions. The photoluminescent properties of a polycrystalline sample of the complex are studied: the luminescence quantum yield is 23%, the excited state lifetime is 0.8 ms. [ABSTRACT FROM AUTHOR]

A new azomethine compound 4-methyl-N-[2-pentafluorophenyliminomethyl)phenyl]methylbenzenesulfamide and a Cu(II) complex based on it are obtained and characterized by 1H NMR, IR spectroscopy and the elemental analysis. Crystal structures of azomethine and its complex are analyzed by single crystal X-ray diffraction (XRD). From the single crystal XRD data it is found that the Cu(II) complex crystallizes in the triclinic space group . The unit cell contains two crystallographically independent mononuclear molecules with similar geometries. In the complex, copper ions have a distorted tetrahedral environment of four nitrogen atoms, which is formed by two bidentate coordinated azomethine ligands. From magnetic measurements it is found that the Cu(II) complex is paramagnetic. [ABSTRACT FROM AUTHOR]

The extension of a series of polyalkylpyrazolyl-substituted 2-imidazoline nitronyl nitroxide radicals LR1/R2/R3 (R = Me, Et, Pr, Bu) enables the synthesis of a number of coordination polymers based on copper(II) bis(hexafluoroacetylacetonate) Cu(hfac)2 with LR1/R2/R3. As compared to breathing crystals (Cu(hfac)2 complexes with monoalkyl-substituted nitroxides LR1 with bridging μ2-O,N coordination), the introduction of the second substituent LR1/R2 into the pyrazole ring allows the performance of the tritopic function of the paramagnetic ligand (μ3-O,O,N) and the formation of 1D and 2D polymers with original structures and different combinations of [CuO6], [CuO5N], [CuO4N2], and [CuO5] coordination cores. Only molecular complexes are obtained with single 3-substituted nitroxide LR1/R2/R3–LMe3. The single crystal X-ray diffraction study of the structures of these compounds shows that as in the case of LMe3, an increase in the size of one of substituents in LR1/R2 to Pr or Bu causes an increase in distances between paramagnetic centers in two- and three-spin exchange clusters, and correspondingly, spin transitions are absent. [ABSTRACT FROM AUTHOR]

Two isostructural mononuclear complexes of lanthanides (Ln = La and Pr) constructed from 1,8-naphthalene dicarboxylate (NDC) and 1,10-phenanthroline (Phen) as auxiliary ligand are reported. Both the complexes were formed through an in situ hydrolytic ring opening reaction of 1,8-naphthalic anhydride with Phen ligands. 3D supramolecular structures are observed which are guided by different weak interactions. The crystal structures of both the complexes were determined by single crystal X-ray diffraction. The room temperature photoluminescence studies, carried out in the powder state displayed three noticeable peaks from excited (3PJ; J = 2, 1, and 0) to ground state (3H4) at ~464 nm, 497 nm, and 538 nm, respectively, under UV excitation. Temperature dependent dc susceptibility (χ = M/H) as a function of temperature is investigated where Pr-complex shows antiferromagnetic behaviour. The Hirshfeld surface analysis of the two complexes is also described. [ABSTRACT FROM AUTHOR]

A mononuclear complex [Zn(phbz)2(phen)] (1, Hphbz = 4-biphenylcarboxylic acid, phen is 1,10-phenanthroline) is obtained, and its structure is determined by single crystal X-ray diffraction (XRD). It is additionally characterized by powder XRD, IR and NMR spectroscopy. The theoretic simulation (DFT B3LYP/Def2-TZVP) of the dimerization process of the complex shows that one of the reasons for the lack of experimental detection of dimeric structures of this type may be a low stabilization energy of the hypothetical binuclear compound [Zn2(phbz)4(phen)2]. [ABSTRACT FROM AUTHOR]

A new Schiff base compound of N′-[(2,6-dichlorophenyl)methylidene]-2-{[3-(trifluoro-methyl)phenyl] amino}benzohydrazide was synthesized and characterized through various spectroscopic techniques, including infrared,1H NMR, 13C NMR spectroscopy and X-ray diffraction. Experimental results collected by XRD were compared with theoretical results obtained from Density functional theory method. Hirshfeld surface analysis was used to obtain three-dimension molecular surface and two-dimension fingerprint plots to illustrate the intermolecular bonding. Theoretical calculations provide valuable insights into both global and local chemical activity, as well as the properties of molecules and chemicals, including their nucleophilic and electrophilic nature. The DFT method at B3LYP/6-311++G(d,p) basis set was employed to study the optimized structure and geometric parameters, as well as to explore the frontier molecular orbitals, global reactive parameters, Mullikan population analaysis, Natural bond orbital and molecular electrostatic potential characteristics which cannot be obtained by experimental methods. Additionally, electrophilicity based charge transfer study was carried out with DNA bases to determine the direction of charge transfer. Finally, an investigation was carried out using molecular docking analysis to examine the binding energies of the title compound with PDB ID: 2QDJ protein target. The analysis yielded significant insights into the possible interactions, offering valuable findings in the process. [ABSTRACT FROM AUTHOR]

We propose a number of approaches for refining unit cell parameters of single crystals using serial laboratory diffractometers equipped with 2D detectors and discuss the corresponding mathematical apparatus for processing the obtained results. The approaches are demonstrated on the example of orthorhombic LiCsMo3O10 crystals grown by the low-gradient Czochralski method using two different seed orientations but being identical in terms of the XRD analysis. It is shown that unit cell parameters of the crystals coincide within the estimated measurement error. The temperature dependence of unit cell parameters in the temperature range 90-450 K is studied, the view of the elements of the thermal expansion tensor is determined. The changes in the structural characteristics of LiCsMo3O10 in the studied temperature range are discussed. [ABSTRACT FROM AUTHOR]

The title compound, C50H42N4NiO6P2·2(ClO4) was synthesized serendipitously by the reaction of Ni(ClO4)2∙6H2O with newly synthesized Schiff base ligand and PPh3 in MeOH and its molecular and crystal structures were determined by single crystal X-ray analysis. It belongs to triclinic system space group with a = 10.7936(4) Å, b = 12.2926(4) Å, c = 19.6272(6) Å, α = 92.574(3)°, β = 95.527(3)°, γ = 102.898(4)°, Z = 2 and V = 2520.73(15) Å3. In the crystal structure, the intra- and intermolecular N–H⋯O hydrogen bonds link the uncoordinated perchlorate anions to the mother molecule. A weak C–H⋯π interaction is also observed. The Hirshfeld surface analysis of the crystal structure indicates that the most important contributions for the crystal packing are from H...H (43.9%), H...O/O...H (30.9%) and H...C/C...H (18.5 %) interactions. Hydrogen bonding and Van der Waals interactions are the dominant interactions in the crystal packing. Analysis of crystal voids showed that there is not any large cavity in the crystal packing. [ABSTRACT FROM AUTHOR]

A quinoline-derived Schiff base ligand, namely 2,5-Dimethyl-N1,N4-bis((quinoline-4-yl)-methylene) benzene-1,4-diamine 1 was characterized by single crystal X-ray structural studies that included a thorough examination of visualizing and investigating intermolecular interactions in molecular crystals via the Hirshfeld surface. The crystal packing of 1 displays intermolecular π∙∙∙π stacking interactions, resulting in a one-dimensional array. The major role of π∙∙∙π stacking interactions in stabilizing the crystal is also supported by the pre-eminence of dispersion energy over the other components in interaction energy calculation and energy framework analysis. The electronic structure of the ligand computed at B3LYP/6-311++G(d,p) level shows a good correlation with the experimentally obtained structure. Additionally, the Fukui function is calculated to identify the electrophilic and nucleophilic active sites in the molecule. [ABSTRACT FROM AUTHOR]

Single crystals of two new inclusion compounds based on porous europium(III) trans-thienothiophenedicarboxylate are obtained by norbornadiene or trans-cinnamyl alcohol substitution for N,N-dimethylformamide (DMF). Their structures and compositions are determined by the single crystal X-ray diffraction analysis. The structure of [Eu2(DMF)4(ttdc)3]·3.3nbd ·1.2H2O (H2ttdc - trans-thienothiophenedicarboxylic acid; nbd - norbornadiene) contains directly localized nbd guest molecules. The π–π stacking interactions are found between the double bonds of norbornadiene and the heterocyclic core of the bridging ligand. The [Eu2(H2O)2(cinol)2(ttdc)3]·cinol compound contains both coordinated and guest molecules of cinnamyl alcohol (cinol). The strongest guest - host contacts without significant stacking interactions appear to be hydrogen bonds between coordinated water molecules and alcohol OH groups. [ABSTRACT FROM AUTHOR]

Molecular and crystal structures of pyrrolo[3,2-b]lup-20(29)-ene-28-carbonitrile are determined. At 100 K single crystals of the C32H46N2 compound are orthorhombic: a = 11.5659(17) Å, b = 14.173(2) Å, c = 16.038(2) Å, V = 2629.1(7) Å3, dcalc = 1.159 g/cm3, Z = 4, space group P212121, dcryst = 1.339 g/cm3. [ABSTRACT FROM AUTHOR]

A new anionic Co(III) complex with 2-[((E)-(2-(ethylamino)-5-nitrophenylimino)methyl)-4-(phenyl diazenyl)]-phenol is prepared and characterized by 1H NMR, IR spectroscopy, and elemental analysis. The crystal structure of the complex is studied by single crystal X-ray diffraction (XRD). From the single crystal XRD data it is found that in the complex, two structurally non-equivalent molecules of the doubly deprotonated ligand are tridentate-chelated by the central Co atom. The cobalt(III) ion is in a slightly distorted octahedral environment of four N and two O atoms. [ABSTRACT FROM AUTHOR]

Complexes [Cd4L4Cl8]·2H2O (I), ZnLCl2 (II), and PdLCl2·CH2Cl2 (III) (L = chiral derivative of 1,10-phenanthroline bearing diisopropylidene glucose) are synthesized. Single crystals of [Cd4L4Cl8] (IV) are prepared. According to the XRD data, the crystal structure of IV consists of molecules of the tetranuclear complex; the coordination number of two terminal and two central Cd2+ ions is 5 (Cl2N3) and 6 (Cl4N2), respectively. In the structure of IV, the L ligand is a bidentate cyclic ligand; Cl atoms exhibit both bridging and monodentate ligand functions. Complexes I–III are characterized by powder XRD and IR spectroscopy. According to the powder XRD data, I is isostructural to IV. Photophysical properties of solid samples of L, I, II are studied. Compound L exhibits excitation-wavelength dependent emission, the excited state lifetimes varying within nano- and microsecond regions. Complexes I and II exhibit ligand-centered photoluminescence. The luminescence quantum yields are as high as 15%. Cytotoxic properties of L, cadmium chloride, and I–III solutions are studied on the human laryngeal carcinoma cell line Hep2. [ABSTRACT FROM AUTHOR]

X-ray diffraction and dielectric studies of the Pb6Sb2O11 phase are conducted using flux-grown single crystals. The crystal structure of the phase is determined for the first time, the role of the lead lone pair is clarified. In the studied temperature (80-940 K) and frequency (0.1-200 kHz) ranges, the temperature-frequency dependences of the dielectric constant ε and the dielectric loss tangent tanδ show no features characteristic of phase transitions. [ABSTRACT FROM AUTHOR]

The diazotization reaction of p-fluoroaniline from aromatic amines with 5,5-dimethylcyclohexane-1,3-dione was studied, as a result 2-(2-(p-fluorophenyl)hydrazone)-5,5-dimethylcyclohexane-1,3-dione (FHDCD) was synthesized and its structure was confirmed by single crystal X-ray diffraction (XRD) technique. The crystal packing was governed by various intermolecular interactions which was inspected by Hirshfeld surface analysis. 2D fingerprint plots were formed to find the contact that has most significant contribution in crystal packing. Enrichment ratio was calculated in order to find the contact that has highest propensity to form crystal packing interaction. Void analysis was carried out to predict the mechanical response of the crystal. Moreover, interaction energy calculations were performed at HF/3-21G electron density model to further inspect the supramolecular assembly of the crystal. [ABSTRACT FROM AUTHOR]

Natural diamonds with a high concentration of nitrogen centers (Kumdykul deposit, North Kazakhstan) are studied. According to the IR spectroscopic data, the concentration of nitrogen C- and A-centers is several hundred ppm at a total concentration above 1000 ppm. At 532 nm excitation the low-temperature photoluminescence (PL) spectra demonstrate dominant luminescence in the 638 nm system, which is caused by negatively charged nitrogen-vacancy (NV–) pairs. The latter is a consequence of a high concentration of donor nitrogen atoms. One electron is transferred from a donor nitrogen atom to the NV pair. Broad bands with maxima at 530 nm and 590 nm correspond to H3 and 575 nm systems: NVN and NV0 complexes. Strong broadening of the diamond Raman line up to 6.5 cm–1 is observed along with the broadening of 503.2 nm, 575.0 nm, and 638.0 nm zero-phonon lines in the PL spectra up to their complete disappearance. This is explained by a high concentration of NVN(H3), NV0, and NV– centers, respectively, as well as structural defects. The unit cell parameters of single crystals are refined by the original procedure. The obtained value of 3.5675(1) Å corresponds (within the measurement error) to the maximum value known for these diamonds. [ABSTRACT FROM AUTHOR]

Three-dimensional coordination polymers Cat2[{Zn4O}2(H2O)2(2,5-I-bdc)7] (1) (2,5-I-bdc = 2,5-diiodoterephthalate, Cat is dimethylammonium) and [Zn2(2,5-I-bdc)2dabco] (2) (dabco is 1,4-diazobicyclo [2.2.2]octane) are prepared. The structures of 1 and 2 are determined by single crystal X-ray diffraction. It is shown that the structure of 2 has a halogen bond between guest DMF molecules and the MOF iodine atom. The I⋯O distances are 2.93-3.03 Å. [ABSTRACT FROM AUTHOR]

A pyranopyrimidine derivative named as 10-amino-7-(2,4-diamino-6-oxidopyrimidin-1-ium-5-yl)-7H-benzo[7,8]chromeno[2,3-d]pyrimidin-9-ium-8-olate dimethylformamide acetic acid hydrate (ADCP) is synthesized by the reaction of 2-hydroxy-1-naphthaldehyde and 2,6-diaminopyrimidin-4-ol in the presence of ethanol and dimethylformamide. The synthesized compound is characterized by single crystal X-ray diffraction technique. The molecule exists as a doubly zwitterion ion and the supramolecular assembly is stabilized by N–H⋯N, N–H⋯O and O–H⋯N bonding interactions. These intermolecular interactions are further investigated and justified by Hirshfeld Surface Analysis. Void analysis is carried out in order to check the response of the crystal to an applied stress. Quantum chemical calculations are carried out at B3LYP/6-31G(d,p) electron density model for finding the interaction energies between molecular pairs. [ABSTRACT FROM AUTHOR]

New oxy-functionalized derivatives are synthesized by ozone oxidation of 1β,13- epoxydihydroquinopimaric acid and methyl ether of 1β-hydroxydihydroquinopimaric acid. Their molecular and crystal structures are determined by the single crystal X-ray diffraction analysis. 1α-Hydroxy-13-isopropyl-7,10a-dimethyl-4-oxooctadecahydro-4b,12-methanochryseno[1,12-bc]furan-7-carboxylic acid (II) is represented by crystalline hydrate of the monoclinic crystal system with the P21 space group, a = 12.3886(6) Å, b = 6.9442(3) Å, c = 13.7037(6) Å, β = 93.290(2)°. The presence of water molecules leads to the formation of a 2D network of hydrogen bonds making molecular layers parallel to (a, b). Crystals of methyl 1β-acetoxy-13-acetyl-7,10a-dimethyl-4-oxohexadecahydro-1H-4b,12-ethenochrysene-7-carboxylate (IV) are orthorhombic, space group P212121, a = 8.3760(3) Å, b = 16.2470(5) Å, c = 18.5603(6) Å. [ABSTRACT FROM AUTHOR]

A novel dinuclear ruthenium(III) ONO pincer complex was synthesized from RuCl3·H2O and 2,6-pyridinedicarboxylic acid (H2pydc) in methanol by using triethylamine as a base. The single crystal XRD disclosed the crystalline nature of the complex that was found to be monoclinic, space group P121/c1, with unit cell dimensions a = 9.4603(7) Å, b = 16.4025(12) Å, c = 6.6844(5) Å, β = 91.839(2)°. The complex showed a rare transoid configuration ′Ru(μ-OMe)2(μ-O2CN)2Ru′ core along with monodentate aqua ligand coordination. To the best of our knowledge, this is a rare case of bridged dinuclear ruthenium complex (only a couple of reports) and the first one containing a pincer ligand. [ABSTRACT FROM AUTHOR]

An efficient method to prepare polymorphs (including the unknown previously) is proposed for tert-butylthiacalix[4]arene tetrasubstituted with ethylcarboxymethyloxy groups at the lower rim by saturating this host and its inclusion compounds by solvent vapors. By means of this method and by heating this calixarene capable of the enantiotropic transition, it is shown that mutual transformations of polymorphs into each other can be controlled. Polymorphs and intermediate saturation products are characterized by a combination of thermogravimetry, differential scanning calorimetry, and powder X-ray diffraction. To reveal factors promoting polymorphism, the structures of two inclusion compounds and one of the polymorphs of calixarene studied are determined by single crystal X-ray diffraction. [ABSTRACT FROM AUTHOR]

From reaction mixture containing the same reagents, the two Cu(II) complexes, with dicyanamide (dca) bridges, [Cu(bpy)(dca)2]n (1) and [Cu(bpy)Cl(dca)]n·H2O (2) (bpy = 2,2′-bipyridine) were prepared. The complexes were characterized by elemental analysis, FTIR spectroscopy and X-ray single crystal techniques. In both complexes, the geometry of the Cu(II) atom is best described as a slightly distorted square pyramidal. A zigzag chain structure is formed in both structures by dca units serving as an end-to-end bridging ligand. In addition, studies on antibacterial activity of the compounds against Gram(+) (Staphylococcus aureus ATCC-6538) and Gram(–) (Escherichia coli ATTC-8739, Pseudomonas aeruginosa ATCC-27853 and Enterobacter aerogenes ATCC-13048) bacteria have been performed using disc-diffusion and microdilution broth techniques. Both complexes were found to be significantly more effective against Gram(–) bacteria E. Coli than against the other bacteria. [ABSTRACT FROM AUTHOR]

The [(Pt(NH3)4)x(Pd(NH3)4)1–x]CrO4 single-phase solid solution (x = 0.5-0.6) is prepared by the cocrystallization of [Pt(NH3)4](NO3)2 and [Pd(NH3)4](NO3)2 aqueous solutions with ammoniac (NH4)2CrO4. The structure and parameters of the tetragonal (I41/amd, Z = 4) unit cell (a = 7.3091(1) Å, c = 15.2720(6) Å) of this compound and the molar fraction of Pt (x = 0.568(7)) are determined using the single-crystal X-ray diffraction method. The unit cell parameters of the studied crystal are additionally refined by an original method (a = 7.3207(9) Å, c = 15.2527(19) Å, V = 817.4(3) Å3) and are further utilized to refine also the molar fraction of Pt using Zen′s law (x = 0.57(1)). A single crystal of [(Pt(NH3)4)0.57(Pd(NH3)4)0.43]CrO4 and two samples of the synthesized product selected from the total mass are thermally decomposed in hydrogen. A study of thermolysis products by XRD, scanning and transmission electron microscopy methods demonstrates the formation of a Pt0.49Pd0.38Cr0.13 nanoalloy included in the Cr2O3 matrix in the form of blocks (~1 µm) and smaller (>2 nm) spherical formations. [ABSTRACT FROM AUTHOR]

A novel organic compound namely, (Z)-3-((2-hydroxypropyl)amino)-N,N-dimethylbut-2-enamide was synthesised by reacting N,N′-dimethylacetoacetamide (DMACAC) and 1-amino-2-propanol. The crystal structure of this compound was determined using single crystal X-ray diffraction method which revealed a planar geometry. Stabilisation of this compound by intramolecular hydrogen bonding is discussed. It was further characterised by TG-DTA, FTIR, NMR and Mass spectrometry. The compound was found to undergo a single step weight loss giving 1.7% residue at 320 °C in a high pure N2 atmosphere and melts in the temperature range of 119-122 °C. [ABSTRACT FROM AUTHOR]

Using a solvothermal method, we have synthesized two coordination polymers of Cu(II). One is a 1D polymer {[Cu(bpy)(NDC)(H2O)]·2H2O}n (1, 1D) formed with 1,8-naphthalene dicarboxylic acid (H2NDC) and 2,2′-bipyridine (bpy) as an auxiliary ligand, while the other is a 2D polymer {[Cu3(TMA) (Imd)3]·5H2O·2DMF}n (2, 2D) formed with trimellitic acid (H3TMA) and imidazole (Imd) as an auxiliary ligand. Both coordination polymers 1 and 2 were formed through an in situ hydrolytic ring opening reaction of 1,8-naphthalic anhydride and trimelitic anhydride with bipyridine and imidazole ligands, respectively. The asymmetric unit of polymer 1 contains asymmetric η1 binding mode (one of the carboxylate) linking distorted square-pyramidal [Cu(NDC)(bpy)(H2O)]2+ coordination units. The syn-syn-η1:η1 linear polymeric conformation exist in the 1D coordination polymer with adjacent Cu...Cu distance is 6.849 Å. A chain of cyclic tetrameric water clusters is present between the stacked layers of the 3D supramolecular structure. The formation of the 3D supramolecular structure is guided by various weak interactions such as O–H...O, C–H...O, C–H...π and π...π interactions. The coordination polymer 2 forms 3D supramolecular architecture guided by various weak interactions such as O–H...O, C–H...O and N–H...O interactions. The crystal structures of both coordination polymers have been determined using single crystal X-ray diffraction and their structural features are described. [ABSTRACT FROM AUTHOR]

Binuclear lanthanide complexes with cucurbit[6]uril (CB[6]), [{Ln(H2O)6}2(μ-CB[6])]Cl6·nH2O (Ln = Yb(1), Eu(2), Tb(3)), are prepared by evaporating a solution containing lanthanide chloride and cucurbit[6]uril. The XRD data for the single crystal of 1 show that the metal in this compound is connected to the macrocycle due to the bidentate coordination of oxygen atoms of cucurbit[6]uril portals to lanthanide(III) cations, leading to the formation of a cationic complex. In the crystal, the [{Ln(H2O)6}2(CB[6])]6+ cations are interconnected by a system of hydrogen bonds. Compounds 1–3 are isostructural. The studied compounds are characterized by IR spectroscopy, thermogravimetric and elemental analyses, X-ray powder diffraction, and luminescence spectroscopy. [ABSTRACT FROM AUTHOR]

The interaction of mono- and tetranuclear hexafluoroacetylacetonates [M4(hfac)4(OMe)4(MeOH)4] (where М = Co, Ni) and [Cu4(hfac)4(OMe)4] with spin-labeled nitrophenols - nitronyl nitroxide 2-(2-hydroxy-5-nitrophenyl)-4,4,5,5-tetramethyl-4,5-dihydro-1H-imidazole-3-oxide-1-oxyl (HL1) or with corresponding iminonitroxide (HL2) - is found to lead to the formation of solvates of binuclear complexes: [Co2(hfac)2(L2)2(H2O)2], [Ni2(hfac)2(L1)2(H2O)2], [Ni2(hfac)2(L2)2(H2O)], [Cu2(hfac)2(L1)2]. The magnetochemical analysis reveals that exchange interactions between metal ions and coordinated nitronyl nitroxides are strongly feroomagnetic and result in the compensation of spins. Imino nitroxide L2 substitution for nitronyl nitroxide L1 changes the character of exchange interactions in the heterospin molecule to the ferromagnetic one. [ABSTRACT FROM AUTHOR]