9.2. Molecular Geometry http://www.ck12.org
AB
The Lewis structure for SF 4 contains four single bonds and a lone pair on the sulfur atom.
The sulfur atom (Figure9.19) has five electron groups around it, which corresponds to the trigonal bipyramidal
domain geometry, as in PCl 5. Recall that the trigonal bipyramidal geometry has three equatorial atoms and two axial
atoms attached to the central atom. Because of the greater repulsion of a lone pair, it is one of the equatorial atoms
that is replaced by a lone pair. The geometry of the molecule is called adistorted tetrahedronorseesaw.
FIGURE 9.19
Sulfur tetrafluoride, SF 4.AB
The Lewis structure of ClF 3 consists of three Cl-F single bonds and two lone pairs on the central chlorine atom.
As in the case of SF 4 , the central atom has five electron groups and a trigonal bipyramidal domain geometry. In ClF 3 ,
both of the bonded pairs that have been replaced with lone pairs are equatorial. The resulting molecular geometry is
calledT-shaped.