State correlation diagram cyclobutene ring opening

Figure 4.7. Disrotatory ring opening of cyclobutene to butadiene a) orbital correlation diagram, b) configuration correlation diagram (dotted lines) and effect of configuration interaction, which converts the diagram into a state correlation diagram (solid lines). The triplet state is indicated by a broken line.

Figure 4.8. Calculated state correlation diagram for the disrotatory ring opening of cyclobutene to butadiene (by permission from Grimbert et al., 1975).

Figure 4.13. Configuration correlation diagram (dotted lines) and the resulting state correlation diagram (solid and broken lines, respectively) for the disrotatory ring opening of cyclobutene, based on natural orbital correlations (by perihission from Bigot, 1980).

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