Abstract
The ability of carbon to form a plethora of compounds through C-C bonding is unique, however, bonding is confined to s and p electrons. Metallic elements on the other hand offer a greater versatility in covalent M-M bonding as they provide s, p, d and f electrons besides the fact that the majority of elements is metallic.
The materials aspect of metal-rich phases is ample. A few structure-property relations will be addressed, e.g. magnetic order and disorder in low-dimensional and frustrated systems, giant magnetoresistance, superconductivity and low work function.
