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Six pyrimidine derivatives based coordination complexes, namely, [Co(mpd)2(H2O)4]·2H2O (1), [Ni(mpd)2(H2O)4]·2H2O (2), [Co(hta)(H2O)3]·H2O (3), [Ni(hta)(H2O)3]·H2O (4), [Cu(Hhta)2(H2O)2]·3H2O (5) and [Zn(hta)(bpy)2]·2H2O (6) (Hmpd = 7-methylimidazo[1,2-a]- pyrimidine-2,5(1H,3H)-dione; H2hta = 2-(4-hydroxy-6-methylpyrimidin-2-ylthio) acetic acid; bpy = 4,4′-bipyridine) have been synthesized and characterized by elemental analysis, IR spectroscopy, PXRD, thermogravimetric analyses and X-ray crystallography. In the packing structures of the complexes, the hydrogen bonds (H-bonds) play important roles. The isomorphic complexes 1 and 2 show 3D tfz-d topology based on twelve H-bonds. Complex 3 and 4 are also isomorphic, exhibiting an unreported H-bonding 3D topology with 8H-bonds in the packing structure respectively. Complex 5 with fourteen H-bonds presents a H-bonding 3D new topology. {(H2O)4O2} H-bonding clusters in complex 6 link the coordination chains into a H-bonding 3D rtw topology. In addition, the catalytic properties of complex 1–6 are investigated. Compared with the other complexes, complex 5 exhibits the best catalytic performance in the decolorization of methyl blue (MB) and the oxidation of benzyl alcohol to benzaldehyde. Meanwhile, complex 5 also shows antitumor activity against HepG2 cells growth with an inhibition rate of 50.1%.

Electrical and electrochemical properties of a series of metal bisdithiolene ion-pair charge transfer complexes of 1,3-dithiole-2-one-4,5-dithiolate, 1,3-dithiole-2-thione-4,5-dithiolate, 1,3-dithiole-2-selone-4,5-dithiolate, and 5,6-dihydro-1,4-dithiin-2,3-dithiolate ligands with general formula [C] x [ML2] (C=counter cation, such as tetrabutylammonium, tetraethylammonium, and tetramethylammonium; M=Ni, Cu, Zn, Pd, or Pt; x =1, 2 or non-integer; L=ligand) have been studied and compared to each other. The effects of the central chelating metal ion, counter cation, stoichiometry, and the ligand on the electrical and electrochemical behaviour are discussed. A crystal structure of bis(tetrabutylammonium) bis(1,3-dithione-2-one-4,5-dithiolato)zincate(II) is determined and compared with its analog compounds. Structure–property relationships are discussed.

Synthesis and some properties of two monoadducts of C 60 to TTF (EDT-TTF–C 60 dyad for the ethylenedithio- and DMDT-TTF–C 60 dyad for both methylthio-TTF substituents) and a third compound, in which TTF is linked to two C 60 (C 60 –TTF–C 60 ), are presented. Infrared spectra of the investigated compounds show that the chemical bonding of C 60 to TTF involves the latter in vibrations of the C 60 part, mainly in its tangential vibrations. Some typical bands of the TTF core present distinct temperature anomalies suggesting an inclination of C 60 group(s) in relation to the plane of TTF core, and/or changes in dynamics of molecular groups.

Amino-tri- tert -butyl-phthalocyanine (AmBuPc) was used as the semiconductor thin layers in model Schottky diode and all organic field-effect transistor (OFET). The diode cell showed a rectifying effect with a rectification ratio of 60 at ±3.2 V. The ideality factors were 1.38 in the low voltage region and 3.09 in the high voltage region, respectively. The results of OFET proved that AmBuPc Langmuir–Blodgett (LB) films could be used as the semiconducting layer of OFET, and the OFET could function as a p-channel accumulation device. From the OFET electrical characteristics, the channel carrier mobility is calculated to be about 5.2×10 −6 cm 2 V −1 s −1 , which is higher than that of vacuum-deposited film OFET (7.8×10 −7 cm 2 V −1 s −1 ) utilizing the same polymer. This phenomenon can be explained as the highly ordered structure of AmBuPc molecules in the LB films. This suggests that a wide conduction channel is able to form in this all organic device, which provides a new method to simplify the fabrication process of OFET and improve their properties.

The electroluminescence (EL) of N,N ′-bis(1-naphthyl)-3,4,9,10-perylenbis(dicarboximide) (BPD) is reported. BPD is an electron acceptor. Red emission from multilayered light-emitting diodes (LEDs) using BPD as light-emitting layer with a maximum brightness of 26 cd/m 2 was observed. The metal materials of the cathode have an effect on both the turn-on voltage and the peaks and shapes of the EL spectra of the devices. This implies that some kind of interaction exists between BPD and the cathode. In LEDs with both hole transport layer and electron transport layer, it was found that the peaks and shapes of the EL spectra of BPD change greatly with the applied bias. When the forward biased voltage is low, the EL emission colour is scarlet. As the voltage increases, the emission colour gradually blue-shifts to reddish orange. Fine structure of the EL spectrum was observed.

Preparation, IR, UV—Vis and X-ray photoelectron spectroscopy (XPS) of three molecular conductors derived from metal complexes of DMID ligand [TBA]0.6[Ni(DMID)2], [TBA]0.44][Ni(DMID)2] and TTF[TBA]0.35[Ni(DMID)2]2 are reported (DMID = 1,3-dithiolene-2-one-4,5-dithiolate, TBA = tetrabutylammonium, TTF = tetrathiafulvalene). Electronic spectra show that the characteristic π-electronic delocalization absorption band over the ligand through π—d interactions in the complexes red-shifts with the increase of oxidization degree. In addition, XPS shows that there is a characteristic ‘satellite’ peak centered at around 168.7 eV, higher by about 4.7–5.4 eV than the main peak, in the S(2p) core-level region spectra of these partially oxidized or charge transfer conductive bisdithiolene metal complexes and, furthermore, the relative intensity of the ‘satellite’ peak increases with the oxidization degree of the complexes.

The synthesis, crystal structure and physical properties of bis(1,1-dithiolene) or bis (1,1-diselenolene) metal complexes of [TBA]2[Ni(i-MNT)2], [TBA][Ni(i-MNT)2] and [TBA]2[Ni(i-MNS)2] (i-MNT = 2,2-dicyanoethylene-1,1-dithiolate,i-MNS = 2, 2-dicyanoethylene-1, 1-diselenolate) were studied and compared to one another or to the related bis (1,2-dithiolene) metal complexes of 5,6-dihydro-1,4-dithiin-2,3-dithiolate, 1,3-dithiole-2-thione-4,5-dithiolate and 1,3-dithiole-2-one-4,5-dithiolate ligands. The structures of the complexes contain equidistant anionic stacks well separated by the counter cation sheets. The planarity and short C-S or C-Se distances in the structures indicate extensive delocalization of the π-system in the compounds. The relative low conductivities for the complexes are due to the low polarizability, large intra-and inter-stack S ··· S distances, and the relative high on-site electron-electron repulsion energy in the compounds.

A new charge-transfer salt containing hexachlorodicuprate (II) binuclear polychloride complex counter anions, ET2Cu2Cl6 (ET = BEDT-TTF = bis (ethylenedithio)-tetrathiafulvalene), was prepared. The room-temperature d.c. conductivity and relative resistance temperature dependence of the salt from room temperature down to 77 K along the longest crystal growth direction are reported. The crystal structure is determined by the X-ray diffraction method at room temperature. It belongs to the triclinicpl space group with crystallographic parameters of a = 11.379(4), b= 16.353(4), c = 9.054(4) A, α = 90.33(3), β= 100.69(3), γ= 100.06(2) °, V= 1628(1) A3, Z = 2, dc = 2.261 g cm−3, λ (Mo Kα) = 0.710 69 A, μ = 28.45 cm−1, F000 = 1104.00 and final R = 0.043, Rw = 0.057 for 2331 observed reflections. The structure consists of isolated ET stacks and the binuclear polychloride complex dianion (Cu2Cl6)2− sheets. In the donor stack, significantly short S···S contacts are observed.

A series of integer or non-integer oxidation-state metal complexes of the multi-sulfur donor ligand 4,5-dimercapto-1,3-dithiole-2-one (DMID) with Ni(II), Cu(II) and Zn(II) has been prepared by precipitating them as tetrabutylammonium, tetraethylammonium, or tetramethylammonium salts. The compounds are characterized by negative-ion fast atom bombardment mass spectral analysis, Fourier transform IR spectral analysis and UV-Vis spectral analysis. Synthetic studies reveal that the stoichiometry of the complex depends not only on the nature of the counter cation, but also on the aerial-oxidation time after the addition of the counter cation and on the nature of the central chelating metal ion. The electronic spectral studies of the complexes with those of related compounds reveal that there are strong π-d interactions in the Ni-chelating species. As an important starting material, the synthesis of 1,3,4,6-tetrathiapentalene-2,5-dione is studied in detail as well.

X-ray photoelectron spectroscopy (XPS) spectra of a series of metal complexes of the DMID ligand [M(DMID) 2 ][TAA] x . (DMID=1,3- dithiole-2-one-4,5-dithiolate, MNi, Cu, Zn; TAA = tetraalkylammonium, such as tetrabutylammonium (TBA), tetraethylammonium (TEA), and tetramethylammonium (TMA); X = integer or non-integer) were studied by comparing with other metal bisdithiolene complexes. The XPS results show that in the metal-DMID complexes the formal oxidation states of the central chelating metal ion are in the valence states of 3+ with the extra negative charge residing essentially on the ligands, especially on the sulfur atoms, and the electron density on the sulfur atoms is higher than that in the electron-rich organic donor molecule tetrathiafulvalene (TTF). Electrical properties of these complexes were investigated by conductivity and cyclic voltammetric measurements. Furthermore, the effects of the central metal atoms, counter cations and ligands on the electrical properties and XPS shifts are discussed.

A study on the electrical switching mechanism in [TBA] x [Ni(dmid) 2 ] thin film materials, in which reproducible current-controlled bistable electrical switching and memory phenomena could be observed [1], by X-ray photoelectron spectroscopy (XPS) was reported. The effects of fabrication electrodes and preparation conditions of the sandwich structure devices on the switching behavior were presented as well.

The structure of a new conductive charge transfer salt was determined by X-ray diffraction method at room temperature. The crystal belongs to monoclinic, space group C 2/c with crystallographic parameters: a=27.817(9), b=4.0295(6), c=22.814(7) A, β=117.98(4)°, V=2258.3(11) A 3 , Z=4, d c =2.626 gcm −3 , λ(MoKα)=0.71069 A, μ=10.86 mm −1 , F(000)=1291.84 and final R=0.076, R w =0.076 for 1652 observed reflections. The structure consists of isolated 3,4;3′,4′-tetra(methylthio)-2,5;2′,5′-tetrathiafulvalene (TTM-TTF) of the organic donors and binuclear non-integer polybromide complex anions. Both the donors and the anions occupy symmetry centers in the cell and the TTM-TTF donors are stacked to form columns along the b axis with the shortest intra- and inter-columnar S···S contacts of 3.214(10) and 3.417(12) A, respectively. 1,1′-di-μ-bromo-2,2′-dibromodicuprate moieties of the binuclear polybromide anions are stacked to form polymeric columns along b, in which the copper atoms are five-coordinate.