  The shear viscosity of a two-dimensional (2D) liquid was calculated using
equilibrium molecular dynamics simulations with a Yukawa potential. The shear
viscosity has a minimum, at a Coulomb coupling parameter of about 17, arising
from the temperature dependence of the kinetic and potential contributions.
Previous calculations of 2D viscosity were less extensive, and for a different
potential. The stress autocorrelation function was found to decay rapidly,
contrary to some earlier work. These results are useful for 2D condensed matter
systems and are compared to a recent dusty plasma experiment.
