The polymerization of styrene at 60 degrees C initiated by 2,2’-azobisisobutyronitrile (AIBN) was studied in N,N-dimethylformamide (DMF) in the presence of tris(bathophenanthroline)iron(III) complex, [Fe(bathophen)(3)](3+). The complex was prepared in situ by mixing hexakis(N,N-dimethylformamide)iron(III) perchlorate with bathophenanthroline (systematic IUPAC nomenclature : 4,7-diphenyl-1,10-phenanthroline) in the molar ratio of 1 : 3. The equilibrium constant for [Fe(DMF)(6)](3+) + 3bathophen reversible arrow [Fe(bathophen)(3)](3+) + 6DMF was 3.12 x 10(3) L(3) mol(-3). The transfer constant for bathophenanthroline was found to be 0.38 +/- 0.01 for the styrene/DMF system at 60 degrees C. Mean velocity constant at 60 degrees C for interaction of polystyryl radical with [Fe(bathophen)(3)](3+) was 3.73 x 10(4) L mol(-1) s(-1).