Abstract Charge–transfer (CT) complexes of pyrimidine Schiff bases, derived from condensation of 2-aminopyrimidine and substituted benzaldehydes, with some aromatic polynitro compounds were prepared and investigated using IR, UV, visible and 1 H NMR spectroscopy. For all solid complexes, the main interaction between the donor and acceptor molecules takes place through the π–π* interaction. Strong and some weak acidic ...