The bismuthide ion is Bi3− but the term is often used to describe less reduced forms of bismuth.
Bismuthides are compounds of bismuth with more electropositive elements.
They all prepared by heating the elements.
[1] In terms of Bi-rich phases, examples are LiBi, KBi2, CaBi3, which exhibit strong Bi-Bi bonding.
The majority of bismuthides adopt efficient packing arrangements and become densely packed structures, which is a characteristic of intermetallic compounds.