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Abstract: A new heterometallic complex [CuMn(5-Brsap)2(MeOH)(Ac)]⋅CH3OH (1) (5-Brsap=5-bromo-2-salicylideneamino-1-propanol) has been synthesized and characterized structurally as well as magnetically. Complex 1 has an alkoxo-bridged Cu(II) and Mn(III) heterobinuclear core, where the Mn(III) and Cu(II) ions have elongated octahedral and square–pyramidal geometries, respectively. In dc magnetic susceptibility measurements reveal that there is strong ferromagnetic interaction between the Mn(III) and Cu(II) ions with an exchange coupling constant J =67.64cm−1. The ac magnetic susceptibility measurements, frequency dependence in both the real and imaginary signals is observed, which indicates slow relaxation of magnetization. An Arrhenius plot gave the effective anisotropy barrier Δ/kB = 11.58K and the pre-exponential factor ι 0 =1.28×10−6 s. [Copyright &y& Elsevier]

Reactions between alkali metal hydrides MH (M = Li, Na, or K) and carbon dioxide (CO 2 ) at room temperature were systematically investigated for the first time. It was found that the raw alkali metal hydrides did not react with CO 2 under static-pressure conditions at room temperature, but the mechanically activated alkali metal hydrides reacted with CO 2 and released large amounts of hydrogen (H 2 ). Under the same ball-milling conditions, the order of reactivity of the alkali metal hydrides with CO 2 was KH > NaH > LiH. The particle size of the activated alkali metal hydrides had a large influence on the reactivity of the alkali metal hydrides with CO 2 . During the reactions, CO 2 was reduced by alkali metal hydrides, generating elemental carbon, alkali metal oxides and H 2 , and it was consumed by alkali metal oxides, forming carbonates. [ABSTRACT FROM AUTHOR]

In this paper, the hydrogen storage properties of the LiNH 2 LiH system doped with K 2 TiF 6 were investigated and discussed. Interestingly, the hydrogen storage properties are significantly enhanced by introducing K 2 TiF 6 into the LiNH 2 LiH system. By doping 5 mol% K 2 TiF 6 in the LiNH 2 LiH system, we obtain the hydrogen desorption peak temperature (233 °C) at a heating rate of 10 °C min −1 , which is approximately 66 °C lower than that of the pristine LiNH 2 LiH system. Moreover, the system begins to desorb H 2 at 75 °C, which is approximately 124 °C lower than in the pristine LiNH 2 LiH system. The isothermal desorption kinetics at 250 °C and 300 °C clearly reflects the dramatically improved kinetic properties. Additionally, the reversibility of the LiNH 2 LiH system can be drastically enhanced by adding K 2 TiF 6 . We propose that the dehydrogenation property of the K 2 TiF 6 -doped LiNH 2 LiH sample is improved by the synergetic effects of K, Ti and F. [ABSTRACT FROM AUTHOR]