Molecular Orbital Theory Flashcards
What is a molecular orbital
A molecular orbital is a particular spatial distribution of electrons in a molecule that is associated with a particular orbital energy. They are not localized on a single atom but extend over the entire molecule, so allow a delocalised picture of bonding.
How can molecular orbitals be formed by the interaction of atomic orbitals
Molecular orbitals are formed by the overlap of atomic orbitals, which can be in phase (bonding) or out of phase (anti-bonding). N atomic orbitals will combine to give N molecular orbitals. Molecular orbitals can also be non-bonding. In order to calculate the molecular orbital wavefunction, a linear combination of atomic orbitals is used as an approximation. There are three types of overlap of atomic orbitals which leads to the formation of molecular orbitals - sigma, pi, and delta.
How can molecular orbitals be used to explain the formation of chemical bonds
Calculation of bond order = 1/2 (bonding - antibonding). This is indicative of the stabilising effect of filling bonding molecular orbitals and the destabilising effect of filling those which are antibonding.
