  We calculate the logarithmic moment of the phonon frequency spectrum at a
single density for 29 monatomic liquids using two methods, both suggested by
Wallace's theory of liquid dynamics: The first method relies on liquid entropy
data, the second on neutron scattering data in the crystal phase. This theory
predicts that for a class of elements called ``normal melters,'' including all
29 of these materials, the two estimates should closely match, and we find that
they agree to within a few percent. We also perform the same calculations for
four ``anomalous melters,'' for which we expect the two estimates to differ
markedly; we find that they disagree by factors almost up to three. From our
results we conclude that the liquid entropy estimates of the logarithmic
moment, applicable both to normal and anomalous melters, are trustworthy to a
few percent, which makes them reliable for use in estimates of various liquid
transport coefficients.
