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The three structures of rare gas inserted fluorohydrides HRgF (Rg=He, Ar, and Kr) with all real frequencies are obtained at the QCISD(T)/aug-cc-pVTZ level. The static first hyperpolarizabilities (β0) at the QCISD/aug-cc-pVQZ level are 8 a.u. (HF), 384 a.u. (HHeF), 737 a.u. (HArF), and 465 a.u. (HKrF). The β0 value remarkably increases by about 50–90 times from 8 a.u. (HF) to 384–737 a.u. (HRgF) due to the inserted rare gas (Rg). The Rg atomic number dependence of β0 for HRgF (Rg=He, Ar, and Kr) is found at the first time. The order of β0 is unmonotonic to be HHeFHKrF, but not monotonic (HHeF

Five new solvent-induced cadmium coordination architectures, {[Cd(bib)(5-Br-H2ip)]·EtOH}n (1), {[Cd0.5(bib)0.5(5-Br-H2ip)0.5]·3H2O}n (2), {[Cd2(bib)(5-Br-H2ip)2(MeOH)]}n (3), {[Cd(bib)0.5(5-Br-H2ip) (H2O)2]·H2O}n (4), and {[Cd(bib)0.5(5-Br-H2ip)(H2O)]}n (5), have been constructed from the same materials (1,4-bis(2-methyl-imidazol-1-yl)butane (bib), 5-bromoisophthalic acid (5-Br-H2ip) and Cd(Ac)2·2H2O) under different reaction solvents. As controlled by solvent systems, compound 1 shows a 3-fold interpenetrating 3D framework based on the left- and right-handed helical chains, while compound 2 reveals a 3-fold interpenetrating 3D network and each single net is based on the left-handed, right-handed and meso-helical chains. Compound 3 is a 3D framework that can be simplified as a 6-connected net with (48·6²) topology. Both 4 and 5 display 3D supramolecular frameworks through weak aromatic π-π stacking interactions and hydrogen bonding interactions. However, the topologies of 4 and 5 are definitely different. Compound 4 presents a 3-connected net with (8²·10) topology, while compound 5 reveals a 4-connected net with (4²·6³·8) topology. The effects of solvents on the crystal structures were discussed and thermogravimetric analysis and solid-state photoluminescence results for 1-5 were investigated. [ABSTRACT FROM AUTHOR]

The characteristic fluorescence properties of quercetin-3- O-rhamnoside (QCRM) and quercetin-3- O-rutinoside (QCRT) were studied in CH3OH–H2O and CH3CN–H2O mixed solvents. Although QCRM and QCRT are known as nonfluorescent molecules, significant fluorescence emissions were discovered at 360 nm in CH3OH and CH3CN when they were promoted to the second excited state. The emission band is broad and structureless and the intensity decreases quickly as the H2O composition in the solvent increases. When the amount of H2O exceeds 60% in both mixed solvents, this emission disappears due to the formation of the distorted excited state. This state will be formed due to the strong intermolecular hydrogen bonding between the polar groups of solute and H2O. As the composition of CH3OH or CH3CN in solvent becomes large, the number of molecules having several intramolecular hydrogen bonding increases. Some of these molecules will be changed to a fluorescent species during the decay process, after excitation. The theoretical calculation further supports these results. The change of the lifetimes, quantum yields, and radiative and nonradiative rate constants of molecules was also examined as a function of solvatochromic parameters for CH3OH–H2O and CH3CN–H2O. [ABSTRACT FROM AUTHOR]

In the title compound, {[Zn(C8H4O4)(C24H16N2)]·H2O} n, the Zn center is coordinated by three O atoms from three different benzene-1,3-dicarboxyl­ate dianions and two N atoms from the bidentate 4,7-diphenyl-1,10-phenanthroline ligand to display a distorted trigonal–bipyramidal geometry. The benzene-1,3-dicarboxyl­ate ligand acts as a μ3-bridge, resulting in a two-dimensional coordination polymer with rhombus-shaped channels. [ABSTRACT FROM AUTHOR]

In the title compound, [Cd(C8H4O4)(C17H10N4O)] n, the CdII atom is six-coordinated by four O atoms from three different benzene-1,3-dicarboxyl­ate (C8H4O42−; 1,3-BDC) ligands and two N atoms from the bidentate 2-furan-2-yl-1 H-imidazo[4,5- f]-1,10-phenanthroline (C17H10N4O) ligand in a distorted octa­hedral geometry. The CdII atoms are bridged by the 1,3-BDC ligands to form a double-chain structure. Neighbouring double chains inter­act through π–π inter­actions, resulting in a two-dimensional network. [ABSTRACT FROM AUTHOR]

In the centrosymmetric title compound, [Zn2(C14H9N2O2)4], each ZnII centre is four-coordinated by two N atoms and two O atoms from three 2-(1 H-benzoimidazol-2-yl)benzoate ligands in a tetra­hedral environment. C—H⋯O and N—H⋯O hydrogen bonds stabilize the crystal structure. [ABSTRACT FROM AUTHOR]

In the title compound, [Zn(C4H2O4)(C14H8N4)]n, the ZnII atom is five-coordinate and exhibits a distorted trigonal-bipyramidal coordination. The ZnII atoms are further bridged by fumarate ligands, forming a two-dimensional network parallel to the ab plane. [ABSTRACT FROM AUTHOR]

In the title complex, [Cu2(C8H4O4)2(C6H6N2O)4]·3H2O, the CuII atom exhibits distorted trigonal–bipyramidal geometry and is coordinated by two N atoms of two isonicotinamide (inta) ligands and three O atoms of three isophthalate (ipt) ligands. C—H⋯O and N—H⋯O hydrogen bonds, as well as π–π stacking inter­actions, are observed between. [ABSTRACT FROM AUTHOR]

The article focuses on the cross-coupling reaction of iridium catalysis through vinyl carbon-hydrogen (C-H) bond activation. It mentions that X-ray analysis and nuclear magnetic resonance (NMR) study were employed to observe the bond formation. It also poses the scheme and tables which summarize the reaction mechanism of cross-coupling and Heck reaction.

In the title compound, [Co(C6H6N2O)2(H2O)4](C8H4O4)·2H2O, the CoII atom (site symmetry ) exhibits a slightly distorted trans-CoN2O4 octa­hedral coordination geometry arising from two N-bonded isonicotinamide mol­ecules and four O atoms of water mol­ecules. The uncoordinated centrosymmetric terephthalate anion and uncoordinated water mol­ecules inter­act with the cation by way of O—H⋯O and N—H⋯O hydrogen bonds, generating a three-dimensional network. [ABSTRACT FROM AUTHOR]

The title inorganic–organic hybrid, {(C7H18N5)2[Mo8O27]·6H2O} n, features polyoxomolybdate chains with neighboring [Mo8O27]6− subunits, each lying on an inversion center, sharing an O atom. These polyanionic chains together with the organic cations and the water mol­ecules are linked together by hydrogen bonds to form a three-dimensional network. [ABSTRACT FROM AUTHOR]

In the title compound, {[Cu(C14H8O5)(C14H8N4)]·H2O} n, the CuII atom adopts a distorted cis-CuN2O2 square-planar coordination geometry. 4,4′-Oxydibenzoate ( L) ligands link the CuII atoms, generating a helical chain. Neighbouring chains are linked through π–π interactions between pyrazino[2,3- f][1,10]phenanthroline ligands with a centroid–centroid distance of ca 3.44 Å, resulting in a two-dimensional supramolecular structure. The structure is completed by O—H...O hydrogen bonds. [ABSTRACT FROM AUTHOR]

In the title molecule, C17H14O4, all non-H atoms are essentially coplanar. The crystal structure is stabilized by weak intermolecular C—H...O hydrogen bonds. [ABSTRACT FROM AUTHOR]

The Co atom in the title compound, [Co(C6H5N2O4)2(H2O)2], is located on an inversion centre and exhibits a distorted octahedral geometry. It is trans coordinated by two N, O-bidentate 5-carboxy-2-methyl-1 H-imidazole-4-carboxylate monoanionic ligands with two water molecules in the axial positions. Each ligand is stabilized by a strong, almost symmetrical, hydrogen bond. Intermolecular N—H...O hydrogen bonds link the molecules into layers, which are further linked into a three-dimensional supramolecular framework through O—H...O hydrogen-bonding interactions involving the water molecules. [ABSTRACT FROM AUTHOR]

In the title compound, bis­(μ-pyridine-2,5-dicarboxyl­ato)bis­[aqua­(pyrazino[2,3- f][1,10]phenanthroline)manganese(II)] dihydrate, [Mn2(C7H3NO4)2(C14H8N4)2(H2O)2]·2H2O, each MnII atom is six-coordinated by three N atoms from one bidentate pyrazino[2,3- f][1,10]phenanthroline and one monodentate pyridine-2,5-dicarboxyl­ate ligand, and three O atoms from two monodentate pyridine-2,5-dicarboxyl­ate ligands and one water mol­ecule. The two MnII atoms are bridged by two pyridine-2,5-dicarboxyl­ate ligands, forming a centrosymmetric dinuclear molecule. Neighboring mol­ecules inter­act through π–π contacts, leading to a one-dimensional supra­molecular structure, and O—H⋯O hydrogen bonds complete the structure. [ABSTRACT FROM AUTHOR]

In the title compound, [Cu2Cl2(C8H4O4)(C18H10N4)2], the CuII atom is four-coordinated by two N atoms from one bidentate dipyrido[3,2- a:2′,3′- c]phenazine ligand, one Cl− anion and one O atom from the benzene-1,4-dicarboxyl­ate ligand. The complete benzene-1,4-dicarboxyl­ate ligand is generated by inversion symmetry, leading to a dinuclear complex. Neighbouring mol­ecules inter­act through π–π stacking, resulting in a two-dimensional supra­molecular structure. [ABSTRACT FROM AUTHOR]

In the title compound, [Cu(C19H11N4)2(H2O)]·2H2O or [Cu( L)2(H2O)]·2H2O, where H L is 2-phenyl-1 H-1,3,7,8,-tetra­azacyclo­penta­[ l]phenanthrene, the CuII atom is five-coord­inated by four N atoms from two L− ligands and one O atom from one water mol­ecule. A three-dimensional supra­molecular structure is formed through π–π and hydrogen-bonding inter­actions. [ABSTRACT FROM AUTHOR]

The title complex, [Cu2(C16H10NO2)4(H2O)2], has a centrosymmetric wheel-shaped dinuclear structure in which two symmetry-related CuII centers are bridged by four carboxyl­ate groups of distinct 2-phenylquinoline-4-carboxyl­ate (phqc) ligands, the Cu—Cu separation being 2.6507 (12) Å. Each CuII center is five-coordinated by four O atoms of carboxyl­ate groups in the basal plane and one O atom of a water mol­ecule in the apical position. In addition, the dinuclear mol­ecules are linked by inter­molecular O—H⋯N hydrogen bonds to form a one-dimensional supramolecular chain. [ABSTRACT FROM AUTHOR]

The title complex, [Co(C10H6NO2)2(CH4O)2], is a neutral mononuclear complex containing a CoII ion in a six-coordinate environment. The CoII center, located on a crystallographic center of symmetry, displays a slightly distorted octa­hedral geometry, with two quinoline-8-carboxyl­ate and two methanol ligands in trans configurations. The complex mol­ecules are linked together by O—H⋯O and C—H⋯O hydrogen bonds between methanol mol­ecules and carboxyl­ate groups to form a three-dimensional framework. [ABSTRACT FROM AUTHOR]

In the original report by Li, Liu, Gao & Che [ Acta Cryst. (2005), E 61, m1705–m1707], the hydrogen-bond D⋯ A parameters were published without their associated s.u. values. The correct Table is given below. [ABSTRACT FROM AUTHOR]

In the title compound, [Zn(1,4-BDC)(L)]n, where 1,4-BDC is the benzene-1,4-dicarboxylate dianion, C7H3O4N2-, and L is dipyrido[3,2-a:2',3'-c]-phenazine, C18H10N4, each ZnII atom is five-coordinated by two N atoms (from one dipyrido[3,2-a:2',3'-c]phenazine ligand) and three O atoms (from two monodentate benzene-1,4-dicarboxylate ligands and one water molecule). The ZnII atoms are bridged by benzene-1,4-dicarboxylate ligands, forming a one-dimensional chain structure. Neighboring one-dimensional chains interact through π-π contacts, leading to a two-dimensional supramolecular structure, and O—H…O hydrogen bonds complete the structure. [ABSTRACT FROM AUTHOR]

The title compound, C28H22O2, is a inter­mediate in the synthesis of 10,10′-dibromo-9,9′-bianthracen­yl. The mol­ecule forms both intra- and inter­molecular O—H⋯O hydrogen bonds. [ABSTRACT FROM AUTHOR]

Novel monodispersed pompon-like magnetite/chitosan (Fe3O4/CS) composite nanoparticles were synthesized by a solvothermal method and used as adsorbents for the removal of toxic sodium pentachlorophenate (PCP-Na) from aqueous media. The adsorption behavior of PCP-Na on Fe3O4/CS obeyed the Langmuir isotherm and fitted the pseudo-second-order kinetics model. Thermodynamic parameters showed that the adsorption process was exothermic and spontaneous. Moreover, the adsorption was strongly pH-dependent. The results of XPS, thermodynamics, pH-dependent and desorption studies suggested that electrostatic attraction, hydrogen bonding and π-π interactions were all believed to play a role in PCP-Na adsorption on Fe3O4/CS. Having a saturation magnetization of 22.2 emu . g-1, the Fe3O4/CS can be easily separated from water with magnets within 2 min. The adsorption equilibrium was achieved quite rapidly (within 30 min) and the maximum removal of PCPNa (91.5%) was obtained at 25 °C and pH 6.5. The Fe3O4/CS investigated can be used to remove PCPNa and other contaminants from wastewater. [ABSTRACT FROM AUTHOR]

The asymmetric unit of the title compound, C14H13N3O3·H2O, consists of one 4-hydr­oxy-3-methoxy­benzaldehyde nicotinoylhydrazone (NAHZ) mol­ecule and one water mol­ecule linked through hydrogen bonds. [ABSTRACT FROM AUTHOR]

In the title compound, [Co(C10H7NO2)2(H2O)2], the CoII ion lies on an inversion centre. It has a distorted octa­hedral geometry and is coordinated by two N, O-bidentate 5-phenyl-1 H-pyrazole-3-carboxyl­ate ligands and two water mol­ecules. Inter­molecular O—H⋯O and N—H⋯O hydrogen bonds link mol­ecules into layers parallel to the (010) plane. [ABSTRACT FROM AUTHOR]

In the title compound, [Cd(C6H7N2O5)2], the Cd atom lies on an inversion center and has a slightly distorted octa­hedral geometry. The equatorial plane contains two bidentate 5-carb­oxy-2-methyl-1 H-imidazole-4-carboxyl­ate monoanionic ligands. Two coordinated water mol­ecules occupy the axial sites. Inter­molecular N—H⋯O hydrogen bonds link the mol­ecules into chains, which are further connected by inter­molecular O—H⋯O hydrogen bonds, resulting in a three-dimensional supra­molecular framework. [ABSTRACT FROM AUTHOR]

The aggregation of V-shaped hydroxypyrimidine derivatives is formed through an intermolecular hydrogen bond in chloroform that cannot form a hydrogen bond with the solute, giving rise to a large enhancement of the two-photon absorption and two-photon induced fluorescence. [ABSTRACT FROM AUTHOR]

In the title compound, [Fe2(SO4)2(C18H10N4)2(H2O)4]·H2O, the FeII atoms are octa­hedrally coordinated by two N atoms from one bidentate dipyrido[3,2-a:2′,3′-c]phenazine (dppz) ligand, two O atoms belonging to two SO42− anions and two water O atoms. The two crystallographically independent dinuclear complex mol­ecules are both generated by inversion symmetry with the sulfate ions acting as bridges. Neighbouring dinuclear complexes inter­act via O—H⋯O hydrogen bonds, leading to a chain structure. [ABSTRACT FROM AUTHOR]

In the title mol­ecule, C14H11NO3S, the benzoisothiazole ring system and the benzyl group form a dihedral angle of 87.7 (9)°. The crystal structure is stabilized by weak inter­molecular C—H⋯O hydrogen bonds. [ABSTRACT FROM AUTHOR]

Describes the crystal structure of an organic compound which is an intermediate in the synthesis of corresponding heterocyclic compounds. Intramolecular hydrogen bond; Z,Z conformation; Gauche formation; Nitrogen atoms; Molecular structure; Crystal packing.

In the title compound, (C12H14N)2[CuI3], the asymmetric unit contains two N-propylquinolinium cations which lie on opposite sides of the CuI32− anion. In the anion, Cu—I bond distances lie in the range 2.5161 (13)–2.5529 (12) Å. All of the atoms in the anion are essentially coplanar, with an r.m.s. deviation from the [CuI3]2− mean plane of 0.0001 Å. In the crystal structure, an extensive network of C—H...I hydrogen bonds links the cations and anions into an extended three-dimensional network, with the cations further aggregated through π–π stacking interactions [centroid–centroid distances 3.48 (7) and 3.43 (5) Å]. [ABSTRACT FROM AUTHOR]

In the title compound, {[Mn(C7H3NO4)(C10H8N2)(H2O)]·H2O} n, the Mn(II) atom has a distorted fac-MnN3O3 octahedral coordination geometry, defined by one N, N′-chelating bipyridine molecule, one N-bonded pyridine-3,4-dicarboxylate (pdb) anion, two monodentate O-bonded pdb anions and one water molecule. Adjacent MnII ions are bridged by pairs of pdb ligands to form distinctive squares, which are further linked by other pdb ligands to result in a layered coordination polymer exhibiting a wave-like structure. Hydrogen bonds involving both the coordinated and uncoordinated water molecules help to consolidate the structure. [ABSTRACT FROM AUTHOR]