  We calculate the components of the microscopic pressure tensor as a function
of radial distance r from the centre of a spherical water droplet, modelled
using the TIP4P/2005 potential. To do so, we modify a coarse-graining method
for calculating the microscopic pressure [T. Ikeshoji, B. Hafskjold, and H.
Furuholt, Mol. Simul. 29, 101 (2003)] in order to apply it to a rigid molecular
model of water. As test cases, we study nanodroplets ranging in size from 776
to 2880 molecules at 220 K. Beneath a surface region comprising approximately
two molecular layers, the pressure tensor becomes approximately isotropic and
constant with r. We find that the dependence of the pressure on droplet radius
is that expected from the Young-Laplace equation, despite the small size of the
droplets.
