[1] Julius Maximilian Univ Wurzburg, Expt Phys 6, D-97074 Wurzburg, Germany
[2] Bavarian Ctr Appl Energy Res ZAE Bayern eV, D-97074 Wurzburg, Germany
[3] Bulgarian Acad Sci, Inst Organ Chem, Ctr Phytochem, Sofia 1113, Bulgaria
[4] Univ Nottingham, GSK Carbon Neutral Lab Sustainable Chem, Jubilee Campus, Nottingham NG7 2GG, England
[5] Univ Bayreuth, Expt Phys 2, D-95440 Bayreuth, Germany
[6] Univ Bayreuth, Macromol Chem 1, D-95440 Bayreuth, Germany