Frontier Molecular Orbital Energy: Definition, Significance, and Applications

Frontier molecular orbital energy refers to the energy difference between the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) in a molecule. HOMO and LUMO are the orbitals in a molecule where electrons are most likely to participate in chemical reactions. Therefore, the energy gap between them can be used to predict the chemical reactivity and electron transfer processes of the molecule. A smaller energy gap usually indicates higher reactivity, while a larger energy gap usually indicates lower reactivity. The calculation of frontier molecular orbital energy is crucial for understanding and designing the chemical properties and reactivity of molecules.