  We study surface nanobubbles using molecular dynamics simulation of ternary
(gas, liquid, solid) systems of Lennard-Jones fluids. They form for
sufficiently low gas solubility in the liquid, i.e., for large relative gas
concentration. For strong enough gas-solid attraction, the surface nanobubble
is sitting on a gas layer, which forms in between the liquid and the solid.
This gas layer is the reason for the universality of the contact angle, which
we calculate from the microscopic parameters. Under the present equilibrium
conditions the nanobubbles dissolve within less of a microsecond, consistent
with the view that the experimentally found nanobubbles are stabilized by a
nonequilibrium mechanism.
