1. Brazilian Nanotechnology National Laboratory (LNNano)Brazilian Center for Research in Energy and Materials (CNPEM) P.O. Box 6192 Campinas CEP 13083‐970 SP Brazil
2. Chemistry Institute (IQ)Universidade Estadual de Campinas (UNICAMP) P.O. Box 6154 Campinas CEP 13083‐970 SP Brazil
3. Department of Fundamental ChemistryUniversidade Federal de Pernambuco (UFPE) Cidade, Universitária Recife 50740‐540 PE Brazil
4. Brazilian Synchrotron Light Laboratory (LNLS)Brazilian Center for Research in Energy and Materials (CNPEM) P.O. Box 6192 Campinas CEP 13083‐970 SP Brazil