The Vibronic and Infrared Spectra of Europium Dibenzoylmethane Chelate with Piperidine

The vibronic spectra of europium dibenzoylmethane chelate with piperidine in the neighbourhood of the Do > 7 F 0 line at 293 K and 77 K and the infrared absorption spectra in the region of 20— 200 c m 1 at various temperatures have been studied. I t is shown that all vibrational frequencies obtained from the vibronic spectrum at 77 K can be observed in the infrared spectrum at the same temperature. For the above frequencies we assign some vibrations as belonging to irreducible representations of S4 point group symmetry.