Mercury polycations

Mercury polycations are a group of related polyatomic ions made from the chemical element mercury. They include the mercurous ion  and larger ions with many connected mercury atoms. Some polymer ions are large enough to be considered "infinite". Mercury making polycations gives it very different chemistry and crystal structure compared to related elements like zinc and cadmium.

The mercury atoms are connected by covalent bonds, not the metallic bonds that normally connect atoms of metals like mercury. This is one of the first examples of a metal-metal covalent bond discovered by modern chemistry.

Mercury polycations are found in some minerals.

 References 

Category:Mercury compounds
Category:Cations