The Optical Activity of the Amide Chromophore, I. MO‐Theoretical calculation of the long‐wavelength optical activity of γ‐lactams and of related isoelectronic molecules

The rotational strength of the longest‐wavelength electronic transition in some simple γ‐lactams and some related isoelectronic molecules is calculated using the CNDO‐CI method. Qualitative agreement with experimental values is obtained. In all investigated systems the long‐wavelength transition corresponds to the nπ* transition. A quadrant rule seems to hold for this transition.