Abstract: The excess Helmholtz free energy functional for nonpolar chain-like molecules is formulated in terms of a weighted density approximation (WDA) for short-range interactions and a Weaks–Chandler–Andersen (WCA) approximation and a Barker– enderson (BH) theory for long-range attraction. Within the framework of density functional theory (DFT), vapour–liquid interfacial properties including density profile and surface tension, and vapour–liquid nucleation properties including density profile, work of formation and number of particles are investigated for spherical and chain- like molecules. The obtained vapour– iquid surface tension and the number of particles in critical nucleus for Lennard- Jones (LJ) fluids are consistent with the simulation results. The influences of supersaturation, temperature and chain length on vapour–liquid nucleation properties are discussed. 

Key words: vapour–liquid nucleation, chain like fluids, density functional theory