Self-assembly of b-diketonate (Htta ¼ thenoyl(trifluoro)acetone) and 4,4 0 -azopyridine (Azo-py) with neodymium(III) ions in the presence of methanol resulted in the formation of mononuclear complex [Nd III (TTA) 3 (MeOH) 2 ]$0.5Azo-py (A) in which two asymmetric units are linked by Azo-py through hydrogen bonding via methanol. A reveals near-infrared emission (NIR) centred at about 895 and 1056 nm, in the 10-370 K temperature range, originating from the two emissive transitions on Nd(III) from 4 F 3/2 to 4 I 9/2 and 4 I 11/2 levels, respectively. Furthermore, the NIR luminescence intensity of A at room temperature augments two times upon thermal elimination of one coordinated methanol molecule. The thermally activated A exhibits single centre ratiometric thermometer behaviour in a wide temperature range from 10 to 300 K. Moreover, fluorescence properties of A were compared to another mononuclear complex [Nd III (TTA) 3 (4-OHpy)(H 2 O)] (B). Assembly A also exhibits field-induced slow magnetic relaxation properties with an energy barrier of DE/k B ¼ 19.7(7) K and an attempt time of relaxation, s 0 ¼ 3.7(8) Â 10 À7 s for fresh sample A, and DE/k B ¼ 27.3 K and s 0 ¼ 8.5(0) Â 10 À8 for assembly A after thermal treatment at 370 K.

We report a mixed-valence cobalt(II/III)–octacyanidotungstate(IV/V) magnet, [CoII(H2O)]2[CoIII{μ-(R)-1-(4-pyridyl)ethanol}2][WIV(CN)8][WV(CN)8]·5H2O. Synchrotron-radiation X-ray single crystal structural analysis, infrared spectrum, and density-functional theory (DFT) calculation indicate that this compound has a chiral structure with the P21 space group and both CoII(S = 3/2)–NC–WV(S = 1/2) and CoIII(S = 0)–NC–WIV(S = 0) moieties, which are structurally distinguishable in the crystal structure. Magnetic measurements reveal that this compound exhibits ferromagnetism with a Curie temperature of 11 K and a coercive field of 1500 Oe, which is caused by the coexistence of the superexchange interaction in the CoII–WV chain and double exchange interaction between the chains.

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The self-assembly of cobalt(II) with purine and octacyanidotungstate(V) resultsi nt he formation of the threedimensional Co 3 [W(CN) 8 ] 2 (purine) 2 ·8.5H 2 O( 1)c oordination polymer.T his compound exhibits humidity-inducedv ariation of the number of water molecules of crystallisation leading to ar eversible structuralp hase transition and the alternation of the long-range ferromagnetic ordering temperature from T C = 29 Kf or the pristine assembly (1)t oT C = 49 Kf or the sample stored in al ow-humidity atmosphere (1-deh). This phenomenon can be attributed to ar eversible change in the hydrogen-bonding network resulting in the modification of the local geometrieso fc obalt(II) as well as the cyanido bridges.

The structure of the reactive cobalt complex catalyst for the enantioselective borohydride reduction of ketones was completely determined by ESI-MS, NMR, and X-ray analyses. It was confirmed that as an axial ligand, 1-chlorovinyl group derived from 1,1,1-trichloroethane was attached. Based on the X-ray analysis, two rotamers on cobalt–carbon bond were found in one unit. The obtained 1-chlorovinylcobalt(III) complex was examined for the enantioselective reduction to afford the reduced product in high yield with a high enantioselectivity.

A three-dimensional chiral-structured molecular magnet based on a Co–W bimetal assembly, [CoII(H2O)2][CoII(pyrimidine){(R)-1-(4-pyridyl)ethanol)}]2[WV(CN)8]2·7.5H2O, is synthesized. This compound exhibits a spontaneous magnetization due to ferromagnetic ordering between CoII (S = 3/2) and WV (S = 1/2) with a Curie temperature of 19 K and coercive field of 3600 Oe.

The rationale behind the stereospecific synthesis of a facial isomer of tris(quinolin-8-olate)aluminum (Alq3) is studied by density functional theory (DFT) calculations, which predict the favourable influence of an H3O(+) ion on the distribution ratio between a meridional and a thermodynamically unstable facial isomer.

Measurement of the thermal racemization rates of alkyl cobalt complexes having chirality only at the carbon coordinated directly to cobalt enabled estimation of the activation parameters of the Co–C bond homolysis and the bond dissociation energies. The effects of substituents of the alkyl moiety and axial bases on the Co–C bond dissociation energy are discussed.