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@ibell @ianhbell has requested that I perform Argon viscosity simulations using the Ulrich Deiters potential:

a nice pair potential function is

u(r) = {p0/r * exp(p1 * r) + p2 * exp(p3 * r) + p4} / (1 + p5*r^6)

This can match the ab initio pair potentials of Ar, Kr, Xe very
well, has a reasonable behaviour in the limit r → 0, and is much
faster than the "official" ab initio function with Tang-Tönnies
damping functions. Good values for argon are:

p0 = 3.139616e+07 K Å
p1 = -2.817277e+00 Å^-1
p2 = -2.787276e+03 K
p3 = -5.836970e-01 Å^-1
p4 = -3.413785e+02 K
p5 = 7.371331e-04 Å^-6

The zero and the minimum are at
sigma = 3.355134529 Å
rmin = 3.755227200 Å
umin = -143.4899372 K

This potential should not only give good virial coefficients, but also
good viscosities. But note that this is a pure pair potential! For
simulations at higher densities you have either to add multi-body
corrections (Richard Sadus is working on this) or to use an effective
potential. Lennard-Jones is too repulsive at close distances
(see the attached figure).

The initial state points will be the same as those simulated by Bill: