  Exploiting the effects of quantum interference we put forward an idea of
designing three primary logic gates, OR, AND and NOT, using a benzene molecule.
Under a specific molecule-lead interface geometry, anti-resonant states appear
which play the crucial role for AND and NOT operations, while for OR gate no
such states are required. Our analysis leads to a possibility of designing
logic gates using simple molecular structure which might be significant in the
area of molecular electronics.
