Valence Electron Rules for Three- and Four-membered Atomic Rings: High-row Representative Elements

Valence electron rules are proposed for the stability and instability of three- and four-membered atomic rings of high-row representative elements in the singlet states. Regular polygons with 4N + 2 and 8N + 6 valence electrons are the ground states of three- and four-membered rings, respectively. The rules are not necessarily applicable out of the range of the number of valence electrons (Nve): 4m <= Nve <= 6m for the groups 14–16 and 3m + [1 - (-1)^m]/2 <= Nve <= 6m for the group 13 where m is the number of the ring members.