Bonds and Molecular Graphs

FIGURE 3. Molecular graphs for hydrocarbon molecules. The same numbering system is used in Tables 1 and 2. The bond critical points are denoted by black dots. The structures depicted in this figure are predicted by the quantum mechanical charge distributions using the theory of atoms in molecules 

A calculation that includes electron correlation and yields a bridgehead internuclear separation in [l.l.l]propellane which is in agreement with the experimental value of 1.596 A, still shows the presence of a bridgehead bond critical point and hence the presence of a bridgehead bond. 

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