Abstract
The concept of bond order, based on an idea of Pauling's, was introduced into molecular orbital calculations by Coulson and by Penney. Layered solids can be described as stacks of macromolecules held together by van der Waals forces, and the concept of bond order is useful for the study of the reactions between these solids and adduct gases adsorbed on the surface layers at sites of inhomogeneous mobile electron density such as those produced by periodic lattice distortions and charge-density waves. In this paper the mobile electron bond order for intercalated layered materials is evaluated with the purpose of describing the structural changes produced by the intercalation reaction. The mobile electron bond order in intercalated 1T-TaS2 was obtained using the experimental data obtained in optical transmission and electron diffraction studies.