Abstract
Metallocryptands are inorganic host complexes that contain a central metal ion, around which are arranged three multi-denate ligands capped by a trigonally coordinated d10 transition metal (Pt(0), Pd(0), and Au(1)). These very large cage complexes are capable of incarcerating a variety of metals, metal ions and anions including alkali metal ions, Hg2 2+, Hg0, Tl+, Pb2+ and with modification the halides. Many of the metal-metal interactions within these complexes are shorter than the sum of the respective covalent radii often resulting in complexes that are highly luminescent.