Synthesis, crystal structure, spectra and quantum chemical study on 1-phenyl-3-(4-nitrophenyl)-5-(2-thienyl)-2-pyrazoline.

1-Phenyl-3-(4-nitrophenyl)-5-(2-thienyl)-2-pyrazoline was synthesized and characterized by elemental analysis, IR and X-ray single crystal diffraction. UV-Vis spectra and fluorescence spectra were measured. Density functional theory calculations on the structure of the title compound were performed at the B3LYP/6-311G** level of theory. NPA atomic charge distributions indicate that, although the S atom in the thienyl ring loses coordination capacity, the title compound still may be used as a potential multi-dentate ligand to coordinate with metallic ions. The calculation of the second order optical nonlinearity was carried out. Natural bond orbital analyses indicate that the electronic absorption bands are mainly derived from the contribution of n→π* and π→π* transitions. Fluorescence spectra determination shows that the title compound is a potential orange-light emitting material.

Dy2(SO3)2(SO4)(H2O)2: the first lanthanide mixed sulfate-sulfite inorganic compound.

The first lanthanide mixed sulfate-sulfite inorganic coordination polymer, poly[diaqua-µ(4)-sulfato-di-µ(4)-sulfito-didysprosium(III)], [Dy(2)(SO(3))(2)(SO(4))(H(2)O)(2)](n), has been obtained, in which both sulfate and sulfite groups originate from the disproportionation of S(2)O(3)(2-) under hydrothermal and weakly acidic conditions. The crystal structure of the title compound exhibits a three-dimensional framework. The Dy(III) ion is surrounded by eight O atoms from one water molecule and two sulfate and five sulfite groups. These DyO(8) polyhedra have two shared edges and form an infinite zigzag Dy-O chain. In the bc plane, neighbouring chains are integrated through SO(3) trigonal pyramids, forming a two-dimensional sheet. Along the a-axial direction, the sulfate group, with the central S atom lying on a twofold axis, links adjacent two-dimensional sheets via two S-O-Dy connections, thus generating the three-dimensional framework.

2,7-Dibromo-9,9-bis-[(pyridin-1-ium-4-yl)meth-yl]fluorene dinitrate.

In the title compound, C(25)H(20)Br(2)N(2) (2+)·2NO(3) (-), the cation lies on a twofold rotation axis which imposes disorder of the dibromo-fluorene unit. In addition, the unique nitrate anion is disordered over two general sites of equal occupancy. The crystal structure is stabilized by inter-molecular N-H⋯O hydrogen bonds.

Synthesis, crystal structure and quantum chemical study on 3-phenylamino-4-phenyl-1,2,4-triazole-5-thione.

3-Phenylamino-4-phenyl-1,2,4-triazole-5-thione was synthesized and characterized by elemental analysis, IR and X-ray single crystal diffraction. Density functional theory calculations of the structure, natural bond orbitals, atomic charge distributions and thermodynamic functions of the title compound were performed at B3LYP/ 6-311G** and PBE1PBE/6-311G**levels of theory, respectively. NPA atomic charge distributions indicate that the title compound can be used as a potential multi-dentate ligand to coordinate with various metallic ions. Calculation of the second order optical nonlinearity was also carried out. The thermodynamic properties of C(0)(p,m), S(0)(m) and H(0)(m) were calculated and correlative equations between the thermodynamic properties and temperatures were also obtained.

3-(4-Fluoro-phen-yl)-1-(4-methoxy-phen-yl)prop-2-en-1-one.

The title compound, C(16)H(13)FO(2), was prepared from 4-methoxy-hypnone and 4-fluoro-benzophenone by Claisen-Schmidt condensation. All the bond lengths and bond angles are in normal ranges. The dihedral angle formed by the two benzene rings is 33.49 (2)°. The crystal packing is stabilized by inter-molecular C-H⋯O hydrogen-bonding inter-actions.

(1R,1'S)-1,1'-Dihydr-oxy-1,1'-biisobenzofuran-3,3'(1H,1'H)-dione.

In the title compound, C(16)H(10)O(6), the complete mol-ecule is generated by a crystallographic centre of symmetry. In the crystal, O-H⋯O hydrogen bonds link the mol-ecules into (100) sheets and C-H⋯O links also occur.

A series of host-guest coordination polymers containing viologens: syntheses, crystal structures, thermo/photochromism and factors influencing their thermo/photochromic behaviors.

Responsive molecular chromic materials have shown potential applications in molecular optical switches and sensor devices as they undergo reversible colour changes upon application of external stimuli. Herein, six host-guest coordination polymers 1-6 and one organic supramolecular compound 7 containing viologens have been synthesized under hydrothermal conditions. Compound 1 shows thermochromic behavior with a colour change from green to blue upon heating at 150 °C in air. Compounds 3, 4 and 7 display photochromic behaviors with a colour change from pale yellow to green under UV light, visible light or sunlight. The relationship between their structures and chromic behaviors has been discussed. Thermo/photochromic mechanisms have been investigated by infrared spectroscopy, powder X-ray diffraction analysis, UV-vis absorption spectroscopy, electron paramagnetic resonance spectroscopy, and X-ray photoelectron spectroscopy. The results demonstrate the generation of viologen radicals caused by thermo/photo-induced electron transfer. It is found that compound 4 can be used as an inkless and erasable printing medium. In addition, compounds 3, 4, and 7 can be used as anti-counterfeiting materials for QR codes. Our findings demonstrate the possibility of applying thermo/photochromic coordination polymers in molecular devices.

Synthesis, IR spectra, crystal structure and DFT studies on 1-acetyl-3-(4-chlorophenyl)-5-(4-methylphenyl)-2-pyrazoline.

1-Acetyl-3-(4-chlorophenyl)-5-(4-methylphenyl)-2-pyrazoline has been synthesized and characterized by elemental analysis, IR and X-ray single crystal diffraction. Density functional (DFT) calculations have been carried out for the title compound by using the B3LYP method at the 6-311G** basis set level. The calculated results show that the predicted geometry can reproduce well the structural parameters. Predicted vibrational frequencies have been assigned and compared with experimental IR spectra and they are supported each other. On the basis of vibrational analyses, the thermodynamic properties of the title compound at different temperatures have been calculated, revealing the correlations between C(0)(p, m), S(0)(m), H(0)(m) and temperatures.

A dinuclear CoII complex: bis(mu-dihydrogen phosphato-kappa2O:O')bis[(bipyridine-kappa2N,N')(dihydrogen phosphato-kappaO)cobalt(II)].

The title compound, [Co2(H2PO4)4(C10H8N2)2], is dinuclear, centred on a symmetry centre of the P1 space group. Each Co atom has a distorted square-pyramidal coordination involving two N atoms from a bipyridine molecule and three O atoms from two bridging and one terminal dihydrogen orthophosphate anion. The molecular structure and packing are stabilized by intermolecular hydrogen-bond interactions.