The specific heat of Na_25, as obtained by first-principles molecular dynamics simulations, shows interesting
anomalies above the melting phase-change region: a) It steadily decreases with increasing temperature, an
effect observed also in bulk liquid metals. This trend is explained in terms of the gradual conversion of
vibrational modes into diffusion modes; b) on top of this decreasing trend, the specific heat shows broad
undulations, induced by the temperature-dependent atomic layering in the liquid cluster. Extended liquid metal
surfaces also show atomic layering, but it does not affect the bulk heat capacity. This effect is therefore genuine
of finite atomic systems and should be expected to be quite general in metal clusters.
