Placing of lone pairs in axial/equatorial position If the lone pairs of elections are put on axial or equatorial position such as to minimize the intera-electronic repulsion, and for the same reason in $\ce{SF4}$, the election pair is kept on the equatorial position(at 90 degrees to only two domains), why then in $\ce{BrF5}$ the lone pair is kept on the axial position, when it is at 90 degrees with 4 domains?
There is no axial or equatorial position in an octahedral structure. All places are equivalent and you can put the lone pair on position.