HMOT of Cyclic it Systems

The nodal properties of the MOs follow the familiar patterns with the orbital of lowest kinetic energy at the bottom (no nodes) and highest kinetic energy at the top (greatest number of nodes). 

The coefficients of the MOs can be easily obtained from four simple rules (these rules are for any molecule, although we are presenting them in the context of cyclic hydrocarbons). Our symbolism will continue to be 

The circle mnemonic for determining the tt system molecular orbital diagram for cyclic hydrocarbons at the HOckel level. 

This is the normalization criterion. The sum of the squares of the coefficients for any MO must be 1, when no overlap integral S is considered. 

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