seesaw

[005391550]

In Dr. Lavelle's lecture he mentioned that AX4E is a seesaw because the lone pair will be on the equatorial plane and affect the two axial atoms and be more stable since the other option is having an axial lone pair that affects all three atoms on the equatorial plane. My question is wouldn't the equatorial lone pair also affect the two atoms on the same plane and make the bond angel slightly less than 120?

[Tiffany_Chen 2K]

Yes! The bond angles between the equatorial atoms will actually be less than 120 degrees, as well as less than 90 degree angle between the axial atoms and equatorial atoms.