The distributions of the average mean and Gaussian curvatures of droplet surfaces collected over the 10 ns trajectory for the w/o and w/t/o systems are provided in Figure A and B respectively. For a perfect sphere with radius r = 20 Å, the anticipated average Gaussian curvature, 1 r 2 , is projected to be 0.0025 Å -2 . The droplet significantly deviates from an ideal spherical shape, as evidenced by the broad distributions of mean and Gaussian curvatures, further enhanced by the formation of surface protrusions. The distribution becomes even broader with the addition of the tbp to the droplet surface, which promotes surface heterogeneity and leads to an increase in surface roughness and therefore more value of the surface curvatures.