A lattice dynamical investigation of the Raman and the infrared frequencies of the Dy2Ti2O7 pyrochlore spin ice compound

A short range force constant model has been applied for the first time to investigate the Raman and the infrared frequencies in Dy2Ti2O7 pyrochlore spin ice compound in its cubic phase of space group Fd3m. The calculations of zone center phonons have been made with four stretching and two bending force constants. The calculated values of Raman and infrared frequencies are in good agreement with the observed ones. The contribution of the nearest atomic interaction between Dy and O has been found to be negligible and is quite likely to play an important role in spin ice compound.