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Introduction to Molecular Orbital Theory

Prof. Sylvia M. Draper

Atomic orbitals (s,p,d) as wave functions; their representation as enclosed boundary surfaces and as radial distribution functions. The relationship of these ideas to the Bohr model for atomic hydrogen. Relative energies of these orbitals; orbital angular momentum quantum number in non-hydrogen-like atoms; penetration and shielding.

Hybridisation of atomic orbitals and the hybrids associated with various geometries; VSEPR treatment of molecular structures.

Bonding as the linear combination of atomic orbitals, including non-bonding and anti-bonding interactions. Labelling of molecular orbitals as sigma, pi (g or u), molecular orbital diagrams of homonuclear diatomic molecules of the first and second row of the Periodic Table. Mixing of molecular orbitals in the earlier members of the period and its effect on the relative energies of the resulting molecular orbitals. Molecular orbital treatment approach illustrated by simple molecules including H2O, BeH2 and BCl3. Reactivity of CO in terms of the molecular orbital energy diagram for this molecule.

Lecture Notes (PDF)


Last updated 24 August 2016 by School of Chemistry (Email).