catena-Poly[tris­([mu]₃-acetyl­aceton­ato)nickelate(II)sodium(I)]

The title complex, [NaNi(C₅H₇O₂)₃]_n, contains an anionic tris­(acetyl­acetonato)nickelate(II) unit, [Ni(acac)₃]^- (acac is acetyl­acetonate), with a highly regular octa­hedral coordination geometry. The Ni^II cation lies on a Wyckoff a site, resulting in D₃ symmetry of the anion. Charge balance is provided by sodium cations, which occupy Wyckoff type b sites. Each sodium cation is surrounded by two [Ni(acac)₃]^- anions, each of which is connected to the alkali metal through three O atoms, in a fac configuration. This arrangement leads to the formation of linear [Na{Ni(acac)₃}]_n chains along the c axis. The Ni...Na distance is 2.9211 (10) Å. The title complex is one of the few examples of heterometallic systems based on alkali and transition metal cations bridged by acetyl­acetonate ligands.

The layered structure of poly[[hexa­aqua­([mu]₄-benzene-1,2,4,5-tetra­car­box­yl­ato)dicopper(II)] tetra­hydrate]

The layered polymeric structure of a benzene-1,2,4,5-tetra­carboxyl­ate-Cu complex forms parallelogram-shaped channels.