Ring-puckering quantum states

Since even functions are more affected than odd functions, the variation of rotational constants with ring-puckering quantum states is expected to deviate from the regular dependence shown by planar molecules (e. g. Fig. 2.5 for oxetanone-3). From Eq. (4.2) we see that alteration of the wave functions of the even levels will affect the expectation values of Z2 and Z4 in this equation, primarily Z2, and lead to an irregular pattern for the lowest few levels. 

Figure 10. Ring-puckering quantum states of 1,3-benzodioxole in different flapping and electronic states.

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