Trigonal Pyramidal Definition:
The trigonal pyramidal geometry is a type of atomic arrangement adopted by an atom that has one lone pair and a steric number of 4. In this case, the bonds formed by the central atom are separated from each other by 107°.
Trigonal Pyramidal Explained:
The molecular shape that results when there are 3 sigma bonds, and one lone pair on the center of the atom in the molecule. Therefore, a steric number of 4. Molecules with a tetrahedral electron pair have sp3 hybridization at the central atom.
Example – Ammonia (NH3) is a trigonal pyramidal molecule.