Lattice dynamics of MnCl2

A complete set of measured dispersion branches for the direction T( xi xi 0), Sigma ( eta 00) and Delta (00 xi ) at 300K is presented. Using a simple model which takes advantage of the two-dimensional nature of the crystallographic structure, a reasonable fit to the data was obtained consistent with using only elastic forces between nearest-neighbour rigid atoms. Derived quantities such as the density of states and specific heat are calculated from the model that gives the best fit.