Molecular geometry is associated with the specific
orientation of bonding in atoms. A careful analysis of electron
distributions through the writing of Lewis diagrams will usually
result in correct electron pair and molecular geometry determinations.
Valence Shell Electron Pair Repulsion (VSEPR) theory:
Principle: Electron pairs around a central atom arrange
themselves so that they can be as far apart as possible from
This method gives the electron pair geometry.
The most common geometry types are defined by the number of electron
pairs around an atom. Electron pairs are defined as electrons
in bonds (single, double, or triple), lone pairs, and occasionally
a single unpaired electron. The various geometries are shown
in the graphic on the upper left.