Raman Spectra of Hexagonal Ethylsulfates of Yttrium and of some Rare Earths

Abstract

The phonon Raman spectra of single crystals of Y(C2H5SO4)3•9H2O, Ce(C2H5SO4)3•9H2O, Nd(C2H5SO4)3•9H2O, Sm(C2H5SO4)3•9H2O have been studied at low temperatures with laser excitation. Some information has also been obtained of the compounds of Ho3+ and Er3+. The types of symmetry of the observed modes have been determined and compared with the results of a group theoretical calculation. The internal modes of the C2H5 and SO4 groups and of the H2O molecules can be completely attributed to observed transitions. There is some evidence to attribute the librational modes of the H2O molecules to transitions which show a very pronounced temperature dependence of the line-widths. Reasons for this temperature dependence are discussed. No lines have been found that can be attributed uniquely to electronic transitions.