Optical properties and the crystal structure of anhydrous gadolinium-trichloride

The Raman and i.r. reflection spectra of GdCl3 have been studied in order to estabish the optically active fundamental frequencies. Gd3+−Cl−)-and (Cl−−Cl−)-force constants in GdCl3 and in LaCl3 and PrCl3 have been calculated on the basis of a simple rigid ion model. It is found that the apparently anomalous spectra of GdCl3 may be a result of a stronger (Cl−−Cl−)-coupling constant than in the hexagonal rare earth trichlorides with lower Z on …