Grid Expansion: a Rhombiclike [L4Fe2(Ag2)2] Complex Containing Ag2 Dumbbells at Two Vertices

The pyrazolate-based ditopic ligand HL forms a strongly hydrogen-bonded corner complex dimer [Fe-II(HL)(2)](2)(BF4)(4) (1) with a [2 x 2] gridlike arrangement of four ligand strands. The two empty vertices can then be filled with {Ag-2}(2+) dumbbells, yielding the unprecedented diferric complex [L4Fe2III(BF4)(6) (2) that features a rhombiclike structure with an almost planar hexagon of metal ions.