For the characterization of the samples, the following techniques
and equipment were used: Infrared spectroscopy (IR): The
infrared spectra were registered in an Atimattson Genesis Unicam FTIR spectrometer. In the disk preparation, 95.5 mg of KBr and
0.5 mg of sample were mixed, and infrared spectra were recorded
in the range between 4000 and 400 cm1.