All nine isolated-pentagon-rule isomers of fullerene C-82 were investigated by the DFT method with the B3LYP functional at the 6-31G, 6-31G*, and 6-31+G* levels. The distribution of single, double, and delocalized pi-bonds in the molecules of these isomers is shown for the first time. The obtained results are fully supported by DFT quantum-chemical calculations of electronic and geometrical structures of these isomers. The molecules of isomers 7 (C-3v), 8 (C-3v), and 9 (C-2v) contain some radical substructures (such as the phenalenyl-radical substructure), which indicates that they are unstable and cannot be obtained as empty molecules. Thus, there is a possibility of obtaining them only as endohedral metallofullerenes or exohedral derivatives. Isomers 1 (C-2), 2 (C-s), 4 (C-2), 5 (C-2), and 6 (C-s) with closed electronic shell are supposed to be stable, resembling isomer 3 (C-2), which has just been extracted experimentally as an empty fullerene. We assume they can be produced as empty molecules.