Collective excitations and dynamic structure factor of liquid tellurium

Using the potential function and its derivatives evaluated by Rao and Venka tesh from the experimental structure factors, the longitudinal (omega(L)) a nd transverse (omega(T)) phonon frequencies have been computed through the equations of Takeno and Goda. The omega(L)(k) maximum is found to occur mid way between zero and the first peak of the structure factor. The dynamic st ructure factor has been calculated in the viscoelastic approximation. In th e current correlation function, the position of the maximum of the current density at a particular k is designated as omega(m). omega(m) versus k has been obtained at various wave vectors. The omega(m) versus k exhibits a fla t portion spreading over the three peaks of the complex structure factor of liquid Te even though omega(m)(k) increases slowly with k. omega(m) gives a peak at nearly the same position as omega(L)(k).