Necmi Dege

An experimental and theoretical study on the novel (Z)-1-((naphthalen-2-ylamino)methylene)naphthalen-2(1H)-one crystal

A novel compound has been synthesized, and its structure has been characterized by IR, UV-vis, NMR and X-ray single-crystal determination techniques. The title compound crystallizes in the orthorhombic space group P212121 with a=6.2120(4)Å, b=10.8242(7)Å, c=22.3857(15)Å and Z=4. The crystal structure has intramolecular N-H···O hydrogen bond and C-H···Cg interaction. These hydrogen bonds and interactions are effective in crystal packing. The optimum molecular geometry, conformational analysis, normal mode wavenumbers, infrared and Raman intensities, corresponding vibrational assignments, chemical shift assignments, and thermo-dynamical parameters have been investigated with the help of Density Functional Theory (DFT). Detailed vibrational assignments have been made on the basis of potential energy distribution (PED). In order to understand the electronic transitions of the compound, time dependent DFT (TD-DFT) calculations were performed in gas phase. Also, the dipole moment, linear polarizabilities, anisotropy and first hyperpolarizabilities values have been computed.

The synthesis, characterization and theoretical study on nicotinic acid [1-(2,3-dihydroxyphenyl)methylidene]hydrazide.

In this study, we reported a combined experimental and theoretical study on nicotinic acid [1-(2,3-dihydroxyphenyl)methylidene]hydrazide (C13H11N3O3) molecule. The title compound was prepared and characterized by 1H and 13C FT-NMR, FT-IR and single-crystal X-ray diffraction. The compound crystallizes in the monoclinic space group P2₁/c with a=6.2681(3) Å, b=16.5309(7) Å, c=12.4197(6) Å, α=90°, β=111.603(4)°, γ=90° and Z=4. In addition, the molecular geometry, vibrational frequencies, gauge including atomic orbital (GIAO), continuous set of gauge transformations (CSGT), individual gauges for atoms in molecules (IGAIM) 1H and 13C NMR chemical shift values, natural bond orbital (NBO), nonlinear optical (NLO) and HOMO-LUMO analyses, molecular electrostatic potentials (MEPs) and thermodynamic properties of the title compound in the ground state were investigated by using Hartree-Fock (HF) and density functional theory (DFT/B3LYP) methods with 6-311++G(d,p). Besides, the hardness and electronegativity parameters were obtained from HOMO and LUMO energies. Obtained results indicate that there is a good agreement between the experimental and theoretical data.

The Synthesis, Characterization, Crystal Structure and Photophysical Properties of a New Meso-BODIPY Substituted Phthalonitrile.

A new highly fluorescent difluoroboradipyrromethene (BODIPY) dye (4) bearing an phthalonitrile group at meso-position of the chromophoric core has been synthesized starting from 4-(4-meso-dipyrromethene-phenoxy)phthalonitrile (3) which was prepared by the oxidation of 4-(2-meso-dipyrromethane-phenoxy)phthalonitrile (2). The structural, electronic and photophysical properties of the prepared dye molecule were investigated. The final product exhibit noticeable spectroscopic properties which were examined by its absorption and fluorescence spectra. The original compounds prepared in the reaction pathway were characterized by the combination of FT-IR, 1H and 13C NMR, UV–vis and MS spectral data. It has been calculated; molecular structure, vibrational frequencies, 1H and 13C NMR chemical shifts and HOMO and LUMO energies of the title compound by using B3LYP method with 6-311++G(dp) basis set, as well. The final product (4) was obtained as single crystal which crystallized in the triclinic space group P-1 with a = 9.0490 (8) Å, b = 10.5555 (9) Å, c = 11.7650 (9) Å, α = 77.024 (6)°, β = 74.437 (6)°, γ = 65.211 (6)° and Z = 2. The crystal structure has intermolecular C—H···F weak hydrogen bonds. The singlet oxygen generation ability of the dye (4) was also investigated in different solvents to determine of using in photodynamic therapy (PDT).

Synthesis, structural and spectroscopic evaluations and nonlinear optical properties of 3,5-bis(4-methoxyphenyl)-4,5-dihydro-1H-pyrazole-1-carbothioic O-acid.

In this study, we report a combined experimental and theoretical study on 3,5-bis(4-methoxyphenyl)-4,5-dihydro-1H-pyrazole-1-carbothioic O-acid (C18H18N2O3S) molecule. The compound crystallizes in the trigonal space group R-3 with a=b=27.7151(12) Å, c=12.4866(6) Å, α=β=90.0°, γ=120.0° and Z=18. The crystal packing is stabilized by O-H⋯O and O-H⋯S intermolecular hydrogen bonds. These hydrogen bond interactions are also proved by NBO analysis. A detailed spectroscopic investigation is performed by the application of FT-IR and FT-NMR in addition to the theoretical approaches. Small energy gap between the frontier molecular orbitals is responsible for the nonlinear optical activity of the title molecule.

A third monoclinic polymorph of 3,4,5-trihy­droxy­benzoic acid monohydrate

The title compound, C7H6O5·H2O, is a new polymorph of the structures reported by Jiang et al. (2000 ▶) [Acta Cryst. C56, 594–595] and Okabe et al. (2001 ▶) [Acta Cryst. E57, o764–o766]. The gallic acid molecule is essentially planar (r.m.s. deviation = 0.550 Å). An intramolecular O—H⋯O hydrogen bond occurs in the gallic acid molecule, which is linked to the water molecule by a further O—H⋯O hydrogen bond. In the crystal, the components are linked by O—H⋯O hydrogen bonds. The hydrogen-bonding pattern differs from those reported for the previous polymorphs.

Crystal and molecular structure of (Z)-4-(((Z)-(2-oxonaphthalen-1(2H)-ylidene)methyl)amino)-N-(thiazol-2(3H)-ylidene)benzenesulfonamide

The experimental geometry of the title compound, (Z)-4-(((Z)-(2-oxonaphthalen-1(2H)-ylidene)methyl)amino)-N-(thiazol-2(3H)-ylidene)benzene, C20H15N3O3S2, was characterized by X-ray diffraction analysis (XRD). And also SEM analysis has been done for morphological investigation of the crystal structure. Molecular structure crystallizes in triclinic form, space group P

Copper(II) complex with 6-methylpyridine-2-carboxyclic acid: Experimental and computational study on the XRD, FT-IR and UV–Vis spectra, refractive index, band gap and NLO parameters

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Synthesis, crystal structure and Hirshfeld surface analysis of tetra­aqua­bis­(isonicotinamide-κN1)cobalt(II) fumarate

with a = 9.1398(7), b = 10.1524(7), c = 11.3767(8) Å, α = 114.488°, β = 91.380(6)°, γ = 102.006(6)° and V = 932.44(12) Å3. In the solid state of the molecular structure C–H···O and N–H···O type interactions provide for stabilization.