TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Method: The reaction system containing the substrate and perfluoroalkyl iodide is heated to 200-450 degrees C. The reaction system is a closed system that provides an increased atmospheric pressure upon heating. The reaction system does not comprise a catalyst, a reaction promoter, or solvent. Preferred Components: The perfluoroalkyl iodide is CF3(CF2)n'I. The perfluoroalkyl iodide is trifluoroiodomethane (CF3I), pentafluoroethyl iodide (C2F5I), n-heptafluoropropyl iodide (n-C3F7I), perfluorobutyl Iodide (n-C4F9I), perfluorohexyl iodide (n-C6F13I) or perfluorooctyl iodide (n-C8F17I). The substrate is a polyaromatic hydrocarbon substrate. The polyaromatic hydrocarbon substrate is anthracene, azulene, coronene, fluorene, fluoranthene, naphthalene, pentacene, perylene, phenanthrene, pyrene, tetracene, or triphenylene. The substrate is a polyheterocyclic compound substrate. The polyheterocyclic compound substrate is acridine, beta -carboline, 9H-carbazole, iminodibenzyl, indole, isoquinoline, phenanthridine phenanthroline, phenazine, phenothiazine, quinazoline, or quinoline. The polyaromatic hydrocarbon having at least one perfluoroalkyl substituent formed is a compound selected from 53 compounds as given in the specification e.g. compounds of formulae (i)-(viii). The polyheterocyclic compound having at least one perfluoroalkyl substituent formed is a compound selected from 6 compounds as given in the specification e.g. compounds of formulae (ix) and (x).n'=0-12;R'f=-(CF2)nCF3;n=0-11;m and p=1-3;m' and p'=0-3.In compound (vi), the sum of elements m' and p' is 1-6. In compounds (ix) and (x), the sum of elements m' is 1-5. SPECIFIC COMPOUNDS - Preparation of 48 compounds are specified as polyaromatic hydrocarbon having perfluoroalkyl groups e.g. 1,4,7,10-tetrakis-trifluoromethyl-perylene (iva); 2-trifluoromethyl-naphthalene; 1,3,6,7-tetrakis-trifluoromethyl-naphthalene; 1,3,5-tris-trifluoromethyl-azulene; 1,3,6,8,10-Pentakis-trifluoromethyl-anthracene.    EXAMPLE - No suitable example given.