抄録
The Non-Gaussian corrections have been estimated for liquid argon by using a model in which the motion of a typical atom is analyzed in terms of the dynamics of an “oscillation”, a quasiparticle consisting of the atom plus a surrounding spherical shell representing the collective effect of the instantaneous near neighbours. Tne oscillatory motion of the atom inside the shell is represented by a stochastic Langevin oscillator first used by Rahman, Singwi and Sjolander. As regards the diffusive motion of the atom plus the spherical shell, a Langevin binary collision model is used. Comparison with Rahman’s calculations for liquid argon shows that the agreement of velocity autocorrelation and α2(t) has been considerably improved with the present model in comparison with the earlier Gibbs model.
