VSEPR theory

VSEPR:

  • The structure around a given atom is determined principally by minimizing electron pair repulsions

  • Atoms bonded to the central atom and lone pairs on the central atom will be as far apart as possible

When evaluating 3D shape:

  • Draw lewis structure

  • Count the number of other aatoms bonding to the central atom

  • Count the number of lone of electrons on the central atom

  • Find the resulting shape

  • Consider the effect of lone pair repulsion on bonded pairs

Electron Domain Geometry:

  • Bonding pairs and non-bonding pairs both take “space” and cause repulsion around the central atom

  • The arrangement of the orbitals around the central atoms is called the EDG

  • After that, molecular geometry is determined by what the lone pairs do to the overall shape