Structural Chemistry Tutorial Page
BENT (AX2E, AX2E2)
This is an example of a bent molecule. These molecules are of the form
AX2E or AX2E2. The difference between the two is that AX2E2 has one more
lone pair around the central atom. The effect of these lone pairs on a
molecule is significant. Lone pairs occupy s orbitals, leaving the bonds
or shared electrons in the p orbitals. P orbitals are naturally more
perpendicular. The result is a smaller angle. A good demonstration
of this effect is with NO2 and NO2+. NO2 is a bent molecule; however,
when you remove an electron from it, making it NO2+, the molecule becomes
linear due to the loss of a lone electron. In NO2+, there is no repulsion
taking place between the two O atoms and the lone electron on the central
atom. Sulfur difluoride, SF2, is an AX2E2 species, and it has an angle of 98 degrees. On the other
hand, nitrogen dioxide, NO2, is an AX2E species, and it has an angle of
134 degrees. The additional lone pair on the SF2 molecule makes the angle
smaller.
To zoom, hold "Shift", and hold the left mouse button
moving it across the image. To rotate the molecule manually, hold the
left mouse button and drag it across the picture.
Back to Main Page