Lattice dynamics of superconducting zirconium and hafnium nitride halides -: art. no. 104502

We have performed a study of the Raman active modes of beta-HfNCl, beta-ZrNCl, and beta-ZrNBr and Na-doped beta-HfNCl in various scattering configurations. The experimental values are compared with a lattice dynamical calculation and assigned to definite atomic motions. The variation of the atomic force constants are analyzed as a function of the bond length, relating their relative strength with the atomic characteristics of the compound.