Example Eleven : SF6
     
+
Valance electrons on A
6
+
Sigma electrons from B
6
-
Pi electrons from A
0
+
Donated dative electrons
0
+/-
Charge on molecule
0
     
=
Total
12
     
/2
Number of negative centres
6
-s
Number of lone pairs
0
     
Therefore the shape is Octahedral