COLOR AND TOPOLOGY OF CONJUGATED SYSTEMS

Colour of polymethine dyes is theoretically characterized by topological indices of their end-groups: the effective length and the electron donor ability. These parameters can be calculated and interpreted through various approaches, involving the formalism of graph theory. The account of the electronic interaction is discussed. The principles of molecular design of deeply coloured substances are outlined. The topological method applied to conjugated systems is proved to be effective, though colour - structure dependence in general case appears to be complex and manifold. © 1990.