The electron pairs that surround the core atoms of the molecule are utilized to forecast the shape of the molecule using the VSEPR hypothesis.
The Valence Shell Electron Pair Repulsion Theory, or VSEPR theory, is based on the idea that all atoms have a repulsion between their pairs of valence electrons, and that the atoms will always want to arrange themselves in a way that minimises this repulsion.
The geometry of the resultant molecule is determined by the atom arrangement.
Sidgwick and Powell initially proposed the hypothesis in .
The VSEPR hypothesis assumes that the molecule will take on a form that minimizes electronic repulsion in the valence shell of that atom.