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A new chloranilate compound with 1-(2-fluorophenyl)piperazine has been synthesized and characterized using spectroscopic methods and X-ray diffraction. The atomic arrangement can be described by an H-bonded 3D network, formed by anionic entities, organic cations and H 2 O molecules linked together via N H…O, O H…Cl, C H…Cl and C H…O hydrogen bonds. The vibrational absorption bands of the various characteristic groups of this compound have been identified by infrared spectroscopy. Moreover, the thermal and dielectric analyses have shown that the title compound has a phase transition at 393 K. The surface mapped over the d norm property, highlights the A⋯H (A O, C, Cl and F) as the main intermolecular contacts. On the other hand, the geometry, intermolecular bonds and harmonic vibrational frequencies of the title molecule have been investigated using the B3LYP/6-31G (d, p) method. The stability of the structure obtained, as well as the charge transfer within the molecule, have been confirmed by determining the energies of the HOMO and LUMO levels and the theoretical gap energy. Molecular docking studies of the title compound have also been conducted as part of this study. [ABSTRACT FROM AUTHOR]

Abstract: We wish to report the synthesis of the Ru(II) crown thioether complex, (1,4,7,10,13-pentathiacyclopentadecane)chlororuthenium(II) hexafluorophosphate, [Ru([15]aneS5)Cl](PF6), and a study of its properties utilizing single crystal X-ray diffraction, electronic spectroscopy, NMR spectroscopy, density functional theory calculations and cyclic voltammetry. The crystal structure shows a single [15]aneS5 macrocycle and a chloro ligand coordinated in a distorted octahedral fashion around the ruthenium(II) center. A significant shortening (0.15Å) of the trans Ru–S bond length occurs in this complex compared to the related PPh3 complex (2.4458(10) to 2.283(1)Å) due to the differences in the trans influence of the two ligands. 13C NMR spectroscopy demonstrates that the structure of [Ru([15]aneS5)Cl]+ is retained in solution. As expected for a Ru(II) complex, the electronic absorption spectrum shows two d–d transitions at 402 and 331nm. These are red-shifted compared to hexakis(thioether)ruthenium(II) complexes and consistent with the weaker ligand field effect of the chloro ligand. The electrochemical behavior of the complex in acetonitrile shows a single one-electron reversible oxidation–reduction at +0.722V versus Fc/Fc+ which is assigned as the Ru(II)/Ru(III) couple. DFT calculations for [Ru([15]aneS5)Cl]+ show a HOMO with orbital contributions from a t 2 g type orbital of the Ru ion, a π component from a p orbital of the axial S atom of [15]aneS5, and a p orbital of the chloro ligand while the LUMO consists of orbital contributions of orbital of the Ru center and p orbitals of the four equatorial S donors. [ABSTRACT FROM AUTHOR]

Describes the crystal structure of the organic compound, triethylammonium tetraphenylborate dichloromethane solvate. Distance between ammonium atom H and edge of phenyl ring; Hydrogen bonding; Aromatic rings; Centroids; Intramolecular dihedral angle; Molecular structure.

In the crystal structure of the title compound, C12H28N2O42+·2PF6−, the center of the diprotonated macrocycle 18N2O4-2H2+ (18N2O4-2H2+ is the 1,4,10,13-tetra­oxa-7,16-diazo­nia­cyclo­octa­decane dication) coincides with a crystallographic inversion center. The structure displays N—H⋯F inter­actions between H atoms of the cationic N atoms of the macrocycle and the F atoms of the PF6− anions. The H⋯F distances are in the range 2.15 (3)–2.42 (4) Å. The structure is nearly isostructural with the previously determined iodide salt, with PF6− acting as a pseudohalide anion. [ABSTRACT FROM AUTHOR]

Highlights: [•] [Co(dien)2]3+ has been recognized as a molecular receptor for benzoates. [•] The isomeric identification of [Co(dien)2]3+ was done with the help of spectroscopic studies. [•] Binding constants with benzoates were determined by UV–vis titration method in aqueous medium. [•] X-ray study reveals the formation of chains and layers through second-sphere coordination network. [ABSTRACT FROM AUTHOR]

We analyze the electronic and molecular structures for the ground and excited electronic states of aromatic terthiophene (3T), the quinodimethane 3',4'-dibutyl-5,5"-bis(dicyanomethylene)-5,5"-dihydro-2,2':5',2"-terthiophene (3Q), and isologues with the middle ring S-oxidized (3TO2, 3QO2). These represent extremes of electron rich and deficient ground states, often exhibiting complementary properties. Oxidizing the central sulfur atom affects the molecular structure, electron affinity, and photophysical properties of both π systems. The consequences for 3T include de-aromatization of the central thiophene, red-shifting of the electronic absorption spectrum, and lowering of the reduction potential. The electron deficient quinoid 3002 shows an enhancement of electron affinity from reducing the electron-donor ability of sulfur, and a blue-shifting of its electronic absorption spectrum was seen. Fluorescence emission is quenched in the sulfonated terthiophene, and the contrary effect again would be expected upon sulfonation of a quinoid emitter. Raman vibrational spectroscopy, electrochemistry, and UV–vis and fluorescence spectroscopies are analyzed in conjunction with theoretical calculations. [ABSTRACT FROM AUTHOR]