Executive Summary : | Coalescence, the process of two droplets colliding to form larger ones, is a crucial aspect of various applications such as ink-jet printing, micro/nano-fluidics devices, and electric displays. The coalescence mechanism differs depending on the presence of surfactants or ions in the droplet. Electric fields are typically used to control coalescence between droplets. Coalescence on surfaces is complex, with surface roughness and spreading of the three-phase contact line playing a significant role. Free energy change during the process can provide essential information for understanding the coalescence mechanism. Molecular dynamics (MD) simulations are used to examine the structural and dynamical behavior of nanoscale systems and extract thermodynamic parameters. This study aims to explore the coalescence dynamics of two water droplets in the presence of alkanol, anion or cation-based surfactants and ionic liquids. The distribution of surfactants or ionic compounds determines the coalescence rate, and the application of an electric field alters the adsorption of surfactants or ionic salts, making the droplet polarized. |