Steric number 6

The fundamental shape is octahedral and is found with SF₆ and PF₆^-. All positions are equal and with one nonbonding pair AX₅ adopts a square pyramidal structure (example BrF₅ 6, and XeOF₄, where repulsion between the double bond and the lone-pair is minimized  by putting  these trans to each other). While two non-nonbonding pairs are exist they minimize their repulsion (rule ii) by adopting the trans configuration,  giving a square planar molecule (example XeF₄, 7 and ICl₄^-).

Steric number 7

The only simple instances are the pentagonal bipyramidal IF₇ (see diagram. 1. and the ion   that is pentagonal planar, that having two lone-pairs occupying  the axial positions .