Reaction cavity pyramidalization

Thus far, attention has been focused on the guest molecules in their ground states. This is so because it is relatively easy to predict and visualize the geometry and orientation of molecules within reaction cavities based on attractive and repulsive interactions between ground state guest molecules and the host structure. However, electronic excitation frequently lead to changes in molecular geometry and polarizability [97], For example, it is well known that formaldehyde becomes pyramidal upon excitation and the C—O... 

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