[1] Linkoping Univ, Dept Phys & Measurement Technol, SE-58183 Linkoping, Sweden
[2] Univ Fed Rio de Janeiro, Escola Quim, Rio De Janeiro, Brazil
[3] Virginia Commonwealth Univ, Dept Chem, Richmond, VA 23284 USA
[4] Australian Natl Univ, Res Sch Phys Sci & Engn, Canberra, ACT 0200, Australia