When the central atom is surrounded by six things, it has a octahedral geometry, which looks like two sqaure pyramids fused at one base. Unlike the simpler geometries, there are two different bond angles in this molecule between different bonds: 90^o and 180^o.

Type	Bond Angle	Example	Lewis Structure
AX6: Octahedral	90o, 180o	SF6

If one of the bonded atoms is replaced by a lone pair, the molecule assumes a square pyramid geometry, with a 90^o and 180^o angles between the bonds. Removing two gives a square planar geometry, still with 90^o and 180^o angles

Type	Bond Angle	Example	Lewis Structure
AX5E: Square Pyramidal	90o, 180o	ClF5
AX4E2: Square Planar	90o, 180o	XeF4

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