C.-Y. Duan

Triboluminescence and crystal structures of europium(III) complexes

Abstract The triboluminescence of four europium complexes [Eu(TTA) 4 ]Y (TTA: 2-thenoyltrifluoroacetone; complex 1 , Y1: 1,2-dimethylpyridinium; complex 2 , Y2: 1,2,6-trimethylpyridinium; complex 3 , Y3: N -methylisoquinolium; complex 4 , Y4: 4-aminopyridinium) was observed. The triboluminescent spectra of 1 – 4 and the crystal structures of 1 , 3 and 4 were determined. The triboluminescence maxima are all similar to those of their photoluminescence, indicating identical emitting species. The triboluminescent activity of 1 may be correlated with its non-centrosymmetric space group. The disorder of the thienyl rings and CF 3 groups in centrosymmetric 3 and 4 may be responsible for their triboluminescent activities.

Synthesis, crystal structure and triboluminescence spectrum of 1,4-dimethylpyridinium tetrakis (2-thenoyltrifluoroacetonato)europate

Abstract Triboluminescent phenomenon of 1,4-dimethylpyridinium tetrakis(then oyltrifluoroacetonato) europate (1) was firstly observed. Its crystal structure and the triboluminescent spectrum were successfully determined. The crystal is centrosymmetric and the Eu atom exhibits an eight-coordinate tetragonal anti-prismatic geometry. The triboluminescent spectrum of 1 is basically similar to that of photoluminescent spectrum and the observed triboluminescent emission correlates with the disorders of the S atoms and F atoms.

New ion-pair nickel(III) complexes containing [Ni(‘S2’)2] (‘S2’2−=1,2-benzenedithiolate) fragments: synthesis, crystal structure and properties

Abstract Two new ion-pair complexes [1-(4′-fluorobenzyl)pyridinium][Ni(bdt) 2 ] ( 1 ) and [1-(4′-bromobenzyl)pyridinium][Ni(bdt) 2 ] ( 2 ), in which bdt 2− =1,2-benzenedithiolate (‘S 2 ’ 2− ), have been prepared and characterized. X-ray structural analyses showed that 1 and 2 are isostructural, and the anions are centrosymmetric. The 2 non-equiv. anions form different uniform-spaced stacking pattern in 1 and 2 . The magnetic measurements of 1 and 2 indicate ferromagnetic behavior in the antiferromagnetic exchange system, which may arise from spin canting. Cyclovoltammetry revealed two quasi-reversible one-electron steps for 1 and 2 , which are attributed to Ni(IV/III) and Ni(III/II) redox couples.

p-(dimethylamino)benzaldehyde isonicotinoylhydrazone monohydrate

The single-crystal X-ray structure determination of the title compound, C15H16N4O.H2O, reveals that the molecule is in the keto tautomeric form and that the azomethine C=N double bond has the E configuration. The water molecule is hydrogen bonded to the hydrazone molecules to form a network structure in the crystal lattice. The crystal structure is stablilized by N-H⋯O, O-H⋯O and C-H⋯O hydrogen bonds.

p-Nitrobenzaldehyde Nicotinoylhydrazone Monohydrate

The X-ray analysis revealed that the title compound, C 13 H 10 N 4 O 3 .H 2 O, is a practically planar molecule which exists in the keto tautomeric form. The molecules lie parallel to (022) planes and form centrosymmetrically related dimers with possible π interactions. The water molecule bridges the hydrazone molecules of the adjacent stacks through hydrogen bonds and the crystal structure is stabilized by O-H...O, N-H...O and C-H...O hydrogen bonds.

CRYSTAL STRUCTURE AND THERMAL ANALYSIS OF A 4,4′-BIPY-BRIDGED BINUCLEAR ZINC(II) COMPLEX, 2[R2NCS2]2 · Zn(4,4′-BIPY) (R=PIPERIDYL)

Abstract The crystal structure of the title complex 2[R2NCS2]2 · Zn(4,4′-bipy) (R = Piperidyl), 1, revealed that it consists of dimers made up from two crystallographically independent molecules. Each zinc atom in 1 forms a 5-coordinate pseudo-square-based pyramidal arrangement (with four Zn-S and one Zn-N interactions). Bondlengths to Zn with the coordinating atoms are comparable to those in other Zn(II) dithiocarbamate complexes. The piperidine ring has a chair conformation. To allow improved packing, the title complex molecules form an approximately linear arrangement extending along both a and b. TGA showed that 1 is decomposed in two close steps to produce ZnS as identified by residual weight. The complex 1 crystallizes in the monoclinic space group C2/c with cell parameters: a = 22.021(5), b = 22.215(3), c = 17.537(2) Å, β = 93.49(2)°, V = 8563(3) Å3 and Z = 8. The structure was refined by full-matrix least-squares methods to R = 0.067, Rw = 0.114.

Bis[methyl Nβ-(4-methoxyphenylmethylene)dithiocarbazato]nickel(II)

The structure of the title compound, [Ni(C10H11N2OS2)2], has been determined at 173 K. There are two independent complex molecules present in the crystal with two slightly different ligand conformations. Both independent Ni atoms lie on inversion centres.

Molecular packing based on a π-stacked screw via self-assembly

Abstract A new platinum(II) complex, C24H16N10S2Pt·3H2O, bis(4,5-diazafluorene-9-one thiosemicarbazato) platinum(II) trihydrate, has been synthesized. Crystals of it are trigonal, space group P32 with cell parameters of a=10.696(4), c=19.748(6) A and Z=3. The ligands are coordinated to the platinum(II) atom by two imino nitrogen atoms N(3) and N(8), and two sulfur atoms S(1) and S(2) forming a rigid molecular tweezers maintained by intramolecular π–π stacking. Detailed crystal structure analyses exhibit that the one-dimensional 32 screw robust supramolecular aggregate was achieved by intermolecular π–π stacking interaction between the extensive delocalization π-system ligands via self-assembly and the aggregates were linked by hydrogen bonding.

4,5‐Diaza‐9‐fluorenone Isonicotinoylhydrazone Monohydrate

The title compound, C 17 H 11 N 5 O.H 2 O, forms two-dimensional layers parallel to the (101) plane. The dihedral angle between the planes of the diazafluorene moiety and the pyridine ring is 27.74 (4)°. The crystal structure is stabilized by O-H...N, N-H...O, C-H...O and C-H...N hydrogen bonds.

p-Methoxybenzaldehyde Nicotinoylhydrazone Dihydrate

The nearly planar aroylhydrazone molecule of the title compound, C 14 H 13 N 3 O 2 .2H 2 O, exists as the keto tautomer in the solid state with an E configuration across the C=N bond. The crystal structure is stabilized by extensive hydrogen bonding involving the water and the hydrazone molecules.