Raman spectrum of metallic layered compound NbSe2

Abstract Raman spectrum of layer-type compound NbSe 2 has been obtained at liquid nitrogen temperature. The frequencies of the Raman active modes E 2 2g , A 1g and E 1 2g are measured to be 29.6 cm −1 , 230.9 cm −1 and 238.3 cm −1 respectively. The observed second order Raman spectrum of NbSe 2 is very different from the corresponding spectrum of MoS 2 . These results show that the force constants of NbSe 2 are less anisotropic than those of MoS 2 .