Towards a molecule - computer? Resources and technologies to compute within a single molecule

The seminal Aviram-Ratner paper in 1974 had triggered the interest on a future molecular computer technology. In this direction, the first step is to realize a digital logic function with a molecule (Joachim et al., 2000). This requires (1) specific design rules depending on the semiclassical or quantum version of the logic function, (2) specific molecules with an internal board ensuring the function, (3) the board must be equipped with different chemical groups to ensure the portability of the function and its interconnection to users, (4) an atomic scale technology to secure user-molecule data & synchro signals exchange, the so-called nanocommunication problem. Finally, (5) production may not be solid state like as compared with micro (and nano)-electronic because of environmental concerns (Khuer and Williams, 2003). We review all those steps providing the state of the art in each case.