Raman spectra of several layer compounds with charge density waves

Raman scattering studies of the transition metal dichalcogenide layer compounds 1TTaS2, 1TTaSe2, 2H-TaSe2 and 1TVSe2 are reported. The materials were studied with commensurate and incommensurate charge density waves (CDWs) as well as in the absence of CDWs. Large qualitative changes observed in the Raman spectra are associated with the formation of CDWs and the change from an incommensurate to a commensurate phase. © 1976.