Diaqua­bis(5-carb­oxy-2-methyl-1H-imidazole-4-carboxyl­ato-κ2 N 3,O 4)cobalt(II) dimethyl­formamide disolvate

In the title compound, [Co(C6H5N2O4)2(H2O)2]·2C3H7NO, the CoII ion lies on an inversion center and adopts a slightly distorted CoN2O4 octa­hedral geometry binding two bidentate chelating 5-carb­oxy-2-methyl-1H-imidazole-4-carboxyl­ate (H2MIDA−) monoanionic ligands and two axial aqua ligands. In the crystal structure, inter­molecular O—H⋯O hydrogen bonds link neighboring mol­ecules, generating a two-dimensional framework containing eight-membered H4O4 rings. In addition, the dimethyl­formamide solvent mol­ecules are hydrogen bonded to the two-dimensional framework via the NH groups of the H2MIDA− ligands

Fabrication of FeSe1-x superconducting films with bulk properties

We have fabricated high-quality FeSe1-x superconducting films with a bulk Tc of 11-12 K on different substrates, Al2O3(0001), SrTiO3(100), MgO(100), and LaAlO3(100), by using a pulsed laser deposition technique. All the films were grown at a high substrate temperature of 610 oC, and were preferentially oriented along the (101) direction, the latter being to be a key to fabricating of FeSe1-x superconducting thin films with high Tc. According to the energy dispersive spectroscopy data, the Fe:Se composition ratio was 1:0.90+-0.02. The FeSe1-x film grown on a SrTiO3 substrate showed the best quality with a high upper critical magnetic field [Hc2(0)] of 56 T