Number of Non-Bonding Electron Domains
0
2 3
4
2
X
AX2 Linear
3 X 120 AX3 AXE Trigonal planar Bent or Angular X Total Number of Electron Domains X AXa AXE, AXE Tetrahedral Trigonal pyramidal Bent or Angular X X X X 90 180 X 4 120 X X x X AX5 AXE AXgE2 AXE3 Trigonal bipyramidal Sawhorse or Seesaw T-shape Linear X X 90 X Xm..A.X A X X X X X 90 AX6 AXE, AXE2 AXE3 Octahedral Square pyramidal Square planar T-shape Image from The Chemogenesis Webbook
X
x AXE4 Linear
http://www.meta-synthesis.com/webbook/45_vsepr/VSEPR.htm
Figure 1. Electron Domain Arrangements and Resulting Molecular Geometries.
In this figure, the "AXE" notation is used: "A" donates the central atom, "X" donates a terminal atom, and "E" donates a non-bonding electron pair (shaded region). For example, "AX,E" refers to a molecule with one central atom (A), three terminal atoms (X) and two non-bonding electron pairs (E). It is also a T-shaped molecule.