Tiny orbitals paint intuitive picture of large molecules’ reactivity

Orbitalets – a type of localised molecular orbitals – depict chemical reactivity in large molecules in a more intuitive way than other orbital descriptions.

Like other frontier molecular orbitals, orbitalets express the quantum mechanical nature of electrons in molecules. They help chemists understand compounds’ reactivity and regioselectivity. But in large molecules with many delocalised electrons, the clear picture orbitals paint in smaller molecules can become blurred – it becomes hard to pinpoint the most reactive bonds and their energy. There are ways to force localisation when calculating orbitals, but some can only be applied to one type of compound while others lose important information about orbitals’ energy in the process.