An Inclusion Complex with [Gd(dmf) ₈ ] ³⁺ Ions Encapsulated in Pockets of an Anionic Array of [{Cu ₆ (CN) ₉ } ³⁻ ] ∞ Units; A Cyanide‐Bridged Cu–Gd Layer Structure

Reaction conditions determine the product: The reaction of GdCl3 and pre-formed K[Cu(CN)2] in DMF leads to a lanthanide–transition-metal complex with a layered structure. Treatment of GdCl3 with discrete quantities of CuCN and KCN, however, yields an inclusion complex with [Gd(dmf)8]3+ ions located within “pockets” (see picture) throughout a three-dimensional array of [Cu6(CN)9]3− ions.