WALSH DIAGRAM

A diagram that follows orbital energies as a function of ANGULAR DISTORTIONS is called a Walsh diagram.

A major application of Walsh diagrams is to explain the regularity in structure observed for related molecules having identical numbers of valence electron (i.e. why H₂O and H₂S look similar), and to account for how molecules alter their geometries as their number of electrons or spin state changes.

 Additionally, Walsh diagrams can be used to predict distortions of molecular geometry from knowledge of how the lumo(Lowest Unoccupied Molecular Orbital) affects the homo (Highest Occupied Molecular Orbital) when the molecule experiences geometrical perturbation(change).