Molecular polarizability in the structural studies of halogenated pyrimidines

Abstract

Bond and molecular polarizabilities of 2-amino-4,6-dichloropyrimidine and 2,4,6-trifluoropyrimidine have been evaluated by quantum mechanical δ-function potential model and molecular vibration methods. The longitudinal bond polarizabilities of CC, CCl and CF bonds confirm the earlier view that the 2,4 and 6 carbon atoms of the pyrimidine molecule are aliphatic in nature while the carbon in position five, being in the meta position to each of the nuclear nitrogens, has a certain degree of aromatic character. The results are discussed fully in comparison with X-ray structural data, and chemical reactions.