The barrier to torsion along the central C-C bond of selected polyfluorobiphenyl (PFB), poly-chlorobiphenyl (PCB) and polybromobiphenyl (PBB) congeners of general structure C12H10-nXn (where X=H, F, Cl or Br and 0≤n≤6) was studied by the molecular orbital method using the AM1 formalism. Barrier heights of PCB congeners were related to their toxicity and barrier heights of 2,2 ',6,6 ' -tetrahalobiphenyls were related to the covalent radii of the halogens (rx) as well as to the length of the C-X bond(rc-x).
ASJC Scopus subject areas
- Condensed Matter Physics
- Physical and Theoretical Chemistry