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Abstract: Water dissociation on clean and oxygen-preadsorbed transition metal surfaces was investigated by the DFT-GGA method. The total energy change and the reaction barrier were calculated with respect to the direct and oxygen-assisted cleavage of Of water. The calculated results showed periodic trends for water dissociation on both clean and oxygen-preadsorbed surfaces. On clean surfaces, the chemical activity for water dissociation increases in the order of Au

A new flexible disulfoxide ligand 1,6-bis(benzylsulfinyl)hexane (L), which is a mixture of the meso and rac isomers, was treated with CuII or CdII nitrate and obtained dimeric complex [Cu2(L)3(H2O)2(NO3)4] 2 or [Cd2(L)3(H2O)2(NO3)4] 3. In the reacting system the crystals of meso isomer 1 of L together with 2 or 3 were obtained. 2 and 3 have similar molecular structures. In the neutral dimer, three ligands present two kinds of coordination models: monodentate and bis-monodentate. The neutral dimeric units in 2 and 3 are linked by hydrogen bonds to yield a chain structure. Crystal structures of all three compounds were determined by single-crystal X-ray diffraction methods. Crystal data for 1: monoclinic, space group Cc, a=41.95(2), b=5.132(2), c=8.660(4) A˚, β=94.898(9)°, V=1857.7(15) A˚3, Z=4, final refinement (I>2σ(I)): R1=0.0659, wR2=0.1415. Crystal data for 2: triclinic, space group P–1, a=9.242(4), b=9.539(4), c=21.042(9) A˚, α=83.888(9), β=87.971(8), γ=74.177(9)°, V=1774.6(13) A˚3, Z=2, final refinement (I>2σ(I)): R1=0.0577, wR2=0.0954. Crystal data for 3: triclinic, space group P–1, a=9.203(4), b=9.831(3), c=20.860(7) A˚, α=84.313(6), β=86.432(7), γ=74.188(6)°, V=1805.9(11) A˚3, Z=2, final refinement (I>2σ(I)): R1=0.0548, wR2=0.1192. [Copyright &y& Elsevier]

Abstract: Four new coordination complexes with azole heterocycle ligands bearing acetic acid groups, [Co(L 1 )2]n (1), [CuL 1 N3]n (2), [Cu(L 2 )2·0.5C2H5OH·H2O]n (3) and [Co(L 2 )2]n (4) (here, HL 1 =1H-imidazole-1-yl-acetic acid, HL 2 =1H-benzimidazole-1-yl-acetic acid) have been synthesized and structurally characterized. Single-crystal structure analysis shows that 3 and 4 are 2D complexes with 44-sql topologies, while another 2D complex 1 has a (43)2(46)-kgd topology. And 2 is a 3D complex composed dinuclear μ 1,1-bridging azido CuII entities with distorted rutile topology. The magnetic properties of 1 and 2 have been studied. [Copyright &y& Elsevier]

Metal oxides with hollow structure provide improved cycling performance, superior rate capability, and high specific capacity when used as anode materials for lithium-ion batteries (LIBs). In this work, the as-prepared sample named H–Fe 2 O 3 @N–C was synthesized by simple polypyrrole (PPY) coating on hollow Fe 2 O 3 and subsequent carbonization under N 2 and air. Interestingly, the thermal treatment of hollow Fe 2 O 3 under air at 500 ​°C induces a phase transition of Fe 2 O 3 from maghemite to hematite which is beneficial for the PPY-coated process. The lithium-storage performance of the resulting materials used as anodes was evaluated. The as-prepared H–Fe 2 O 3 @N–C anode shows a high specific capacity (1093.1 ​mA ​h ​g − 1 at a current density of 0.1 ​A ​g − 1) and high cyclic stability (the specific capacity of 501.3 ​mA ​h g−1 was maintained at a current density of 2.0 A g−1 after 700 cycles). The high specific capacity and superior cyclic stability of the prepared anode are attributed to the hollow structure and N -doped carbon coatings that can alleviate the volume variation and reduce the charge-transfer resistance. Hollow Fe 2 O 3 @N-doped carbon was synthesized by simple polypyrrole coating on hollow Fe 2 O 3 and subsequent carbonization under N 2 and air, showing stable cycling performance. [Display omitted] • Fe 2 O 3 @N-doped carbon were synthesized by PPY coating on hollow Fe 2 O 3 then carbonization under N 2 and air. • Thermal treatment of hollow Fe 2 O 3 under air induces a phase transition of Fe 2 O 3 which is beneficial for the PPY-coated process. • The as-prepared anode shows a high specific capacity of 501 ​mA ​h ​g−1 at 2.0 ​A ​g−1 after 700 cycles. [ABSTRACT FROM AUTHOR]