[1] Tech Univ Clausthal, Inst Organ Chem, D-38678 Clausthal Zellerfeld, Germany
[2] Tech Univ Clausthal, Clausthal Ctr Mat Technol, D-38678 Clausthal Zellerfeld, Germany
[3] Helmholtz Zentrum Berlin, Dept Crystallog, D-14109 Berlin, Germany
[4] Univ Leipzig, Inst Mineral Crystallog & Mat Sci, D-04109 Leipzig, Germany