<P> Valence shell electron pair repulsion (VSEPR) theory is a model used in chemistry to predict the geometry of individual molecules from the number of electron pairs surrounding their central atoms . It is also named the Gillespie - Nyholm theory after its two main developers, Ronald Gillespie and Ronald Nyholm . The acronym "VSEPR" is pronounced either "ves - pur" or "vuh - seh - per". </P> <P> The premise of VSEPR is that the valence electron pairs surrounding an atom tend to repel each other and will, therefore, adopt an arrangement that minimizes this repulsion, thus determining the molecule's geometry . Gillespie has emphasized that the electron - electron repulsion due to the Pauli exclusion principle is more important in determining molecular geometry than the electrostatic repulsion . </P>

What is the valence shell electron pair repulsion theory