Thallide

[3] A more general classification is polar intermetallics, as clusters contain delocalized multicentre bonds.

[5] Mixed anion compounds with thallides include halides (bromides and chlorides),[6] oxides,[7] and tetrelates (silicate, germanate).

[8] Thallide compounds can be produced by melting metals together in a tantalum crucible under an inert argon atmosphere.

[3] However if arsenic is included in the mix, it can react with the crucible wall.

Thallide clusters mostly do not follow Wade-Mingos rules or the Zintl–Klemm concept, as they have too small a negative charge.