trigonalplanar

Trigonal Planar

Molecules with 3 VSEPR pairs adopt a trigonal planar VSEPR shape.

BF3 is an example of a molecule with the formula AX3. Its structure is called a trigonal planar. It has three bond pairs (n=3), which adopt an X-A-X angle of 120 to achieve maximum separation from each other.

If one of the positions on the central atom is occupied by a lone pair (n=2 and m=1), the VSEPR formula is AX2E. The VSEPR shape is trigonal planar, and the molecular shape is bent.

If two of the positions on the central atom are occupied by a lone pair (m=2 and n=1), the VSEPR formula is AXE2. The VSEPR shape is trigonal planar, and the molecular shape is linear.