The ions containing four and eight atoms are the most common, but they are by no means the only
cations known for the group VIA elements. Tellurium forms the Te 6
4 ion, which is a slightly distorted
trigonal prism. The Se 102 cation has been studied, and sulfur forms the S 192 ion having a five-atom
chain with a seven-atom ring attached on each end. The use of nonaqueous solvents and superacids
makes it possible to generate many unusual and interesting species.