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Herein, we report the synthesis of the copper-based MOF, Cu3(SDBA)2(HSDBA), using a solvothermal method.

Three crystalline

We report on a new p-type organic semiconductor single crystal, 5,10,15-trimethyl-10,15-dihydro-5H-diindolo[3,2-a:3’,2’-c]carbazole (N-trimethyltriindole). This molecule crystallizes forming a highly ordered columnar structure in which stacked molecules are situated at two alternating distances (3.53 A and 3.68 A) along the column as determined by single crystal X-ray diffraction analysis. These short intermolecular distances between adjacent units, make this system an ideal candidate for charge-transport processes along the stacks. Relevant parameters for transport (i.e. internal reorganization energies, transfer integral) have been estimated by DFT calculations at a 6-311G(d,p)/B3LYP level of theory. As a double check for the transfer integral, the electronic band structure of a one-dimensional stack of molecules has been computed. The electronic properties of this material have been studied both theoretically and experimentally. Its HOMO value is found to coincide with Au work function (ΦAu = 5.1 eV), thus low barriers are expected for hole injection from gold electrodes. The hole mobility of this material has been predicted theoretically considering a hopping-type mechanism for the charge-transport and determined experimentally at the space charge limited current (SCLC) regime of the current–voltage measurements. Both theoretical and experimental values are in good agreement. The high hole mobility (μmin = 0.4 cm2 V−1 s−1) of this material points towards its useful application in the organic electronics arena. N-Trimethyltriindole single crystals constitute an essential model to study transport properties of triindole-based materials and to design new derivatives with improved electronic performance.

The synthesis of organic materials has typically involved linking one or more types of discrete molecular building blocks to produce structures that are extended in three dimensions. For example, repeated addition of monomers results in the formation of organic polymers that have randomly packed structures and therefore form amorphous solid materials. If the building blocks repeat in an ordered sequence, crystalline solids are formed. The properties of the resulting solids are intimately related to both their network structure and their chemical components. On page 365 of this issue, Liu et al. report a material that has a fabric-like woven microstructure, giving it exceptional flexibility ( 1 ).

4,4′-Methylene-bispyrazole (1) crystallizes in the P21/n space group with Z = 4, a = 5.4199(8) A, b = 16.194(6) A, c = 8.381(5) A, β = 98.18(5)°. 4,4′-Methylene-bis (3,5-dimethylpyrazole) (2) crystallizes in the Pbca space group with Z = 8, a = 8.350(3) A, b = 16.078(3) A and c = 17.154(5) A. Finally, 3,3′-bipyrazole (4) crystallizes in the P21/n space group with Z = 2, a = 5.465(2) A, b = 5.491(3) A, c = 10.058(4) A and sol; = 92.88(2)°. The packing adopted by molecules 1 and 2 is related to the disposition of the pyrazole rings. In compound 4, all the molecules are joined to their neighbors by two double hydrogen bond systems forming zigzag chains. Using solid state 13C NMR spectroscopy, no dynamic proton transfer was observed in these crystals, and not on those of 3,5,3′,5′-tetramethyl-4,4′-bipyrazole (3) either.

Salts of the type (NEt3H)[Fe2(CO)6(μ-CO)(μ-SR)] (R=1cr; iPr, tBu, Ph) react with [ClAuPPh3] in the presence of TIBF4 to produce the neutral iron-gold clusters [Fe2(CO)6(μ-CO)(μ-SR)(μ-AuPPh3)] (R=1cr; iPr, 1; R=1cr; tBu, 2; R=1cr; Ph, 3) in high yields. The structure of 1 has been determined by X-ray diffraction methods. Crystals are monoclinic, space group P21/c, with a = 11.373(1), b = 14.899(3), c = 17.997(8) A, β = 95.12(2)° and Z = 4, R = 0.030 and R′ = 0.035 for 3579 unique reflections with I ⩾ 2σ(I). The basic skeleton consists of an Fe2Au triangle where the FeFe bond is bridged by a carbonyl and a thiolate group. In contrast, the reaction of the salts (NEt3H)[Fe2(CO)6(μ-CO)(μ-SR)] (R = Et or C6F5) with [ClAuPPh3] does not afford the corresponding mixed iron-gold clusters, and the diiron mono- or di-substituted complexes [Fe2(CO)5 (PPh3)(μ-SR)2] (R=1cr; Et, 4; R=1cr; C6F5, 5) and [Fe2(CO)4(PPh3)2(μ-SEt)2] (6) are obtained instead. The structure of 4 has been established by single-crystal X-ray diffraction studies. Crystals are triclinic, space group, P 1 , with a = 10.472(4), b = 11.329(2), c = 13.437(2) A, α = 80.34(2), β = 92.62(3), γ = 114.46(2)°, and Z = 2, R = 0.027 and R′ = 0.030 for 3732 unique reflections with I ⩾ 2σ(I). The FeFe bond in 4 is almost symmetrically double-bridged by two thiolate ligands and the phosphine group attached to the Fe(1) is trans to the iron-iron bond.

Summary The synthesis and structural characterization of the title compound are described; its structure consists of corner sharing GaO 6 octahedra, GaO 5 trigonal bipyramids and PO 4 tetrahedra that link to form an open structure containing channels (ca 4 diameter) running along [001].