Unit 3 Topic 2 ✓

A sigma molecular orbital is formed by the end-on overlap of two atomic orbitals along the axis of a covalent bond NOTE: Sigma bonds are stronger than Pi bonds

A pi molecular orbital is formed by side on overlap of two parallel atomic orbitals that are perpendicular to the axis of the covalent bond NOTE: Pi bonds are weaker than Sigma bonds

Constructuve interference between two wave functions results in a Bonding molecular orbital which is in a lower energy, more stable state because the two nuclei are held within the area of electron density

Destructive interference bwteen two wave functions results in an Anti-bonding molecular orbital which has a region of zero electron probability between nuclei. Its in a higher energy, less stable state

Electronegativity is the attraction of an atom involved in a bond for the bonding pair of electrons

Hybridisation is when atomic orbitals mix within an atom to generate new, hybrid orbitals

An alkene is an unsaturated molecule that contains at least one carbon to carbon double bond

A system where there is alternating double and single bonds

HOMO is the highest occupied molecular orbital, it contains electrons with the highest energy

LUMO is the lowest unoccupied molecular orbital, it contains no electrons and has the least energy

A chromophore is a group of atoms in an organic molecule that absorbs photons of light in the visible part of the spectrum