Contact intermolecular transfer, integral

The intermolecular interaction is very sensitive to the anisotropy of the conduction molecular orbitals (HOMO, LUMO,. ..) and the compactness of the intermolecular contacts. So that it may be appropriate to use the anisotropy of the intermolecular overlap integral (5) of the conduction molecular orbitals as a semi-quantitative measure of the dimensionality of the system. If we adopt the simple extended Huckel approximation (transfer integral (t)(xS), we can visualize the dimensionality of the molecular conductor as a form of simple band structure (or the shape of Fermi surface (FS)). 

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