| Abstract: | The PM3 semi-empirical andab initio approximations have been used to calculate the equilibrium geometry and energy levels of donor-acceptor molecules that are derivatives of conjugated amines. Chain lengthening inverts the local level of the unshared nitrogen electron pair and the delocalized level, and also changes the sign of the barrier to rotation of the dimethylamino group in the excited state. Organic Chemistry Institute, Ukrainian National Academy of Sciences, 252660 Kiev 94, ul. Murmanskaya 5, Ukraine. Translated from Teoreticheskaya i éksperimental’naya Khimiya, Vol. 33, No. 4, pp. 224–228, July–August, 1997. |
