Collective dynamics in a liquid polyvalent metal: liquid thallium at the melting point.

Collective dynamics in liquid thallium at the melting point in a wide range of wave numbers and frequencies is studied by molecular dynamics simulations and a theoretical analysis of time correlation functions within the approach of generalized collective modes. The heat fluctuations were explicitly treated in the theoretical scheme within the thermoviscoelastic dynamic model. We report dispersion and damping of generalized longitudinal sound excitations, nonhydrodynamic shear and heat waves, as well as wave number dependence of main relaxation processes. Generalized wave number-dependent thermodynamic quantities and transport coefficients in liquid Tl are discussed.