This study employs molecular dynamics simulations to investigate droplet dynamics when a stationary droplet on a solid surface is struck by another droplet of similar size from above. The focus is on the jumping behavior of the merged droplet and the associated energy conversion. The process is primarily controlled by the amount of energy converted into kinetic energy after dissipation. At high impact velocities, the energy conversion efficiency becomes constant, with only about 1% lost due to surface adhesion-an effect that diminishes with increasing velocity. Factors such as impact velocity, droplet size, surface texture, and wettability significantly influence the jumping velocity. Scaling laws are developed for the maximum spreading time, spreading factor, and restitution coefficient based on the Weber (We) and Reynolds (Re) numbers, which differ from those for single droplet impacts. On superhydrophobic surfaces, the spreading time is approximated as , and its dimensionless form scales linearly with . The general scaling law for the spreading factor is , where for velocity-dependent and for velocity-independent spreading regimes.Graphical abstract Energy Conversion and Jumping Dynamics of Colliding Nanodroplets on Solid Surfaces.
Thermally activated membrane transformations such as lipid exchange, pore formation, and domain growth are commonly described in terms of activation barriers; yet, the molecular origins of their kinetics often remain difficult to establish. Recent results on interfacial lipid exchange, analyzed using the collective small displacements (CSD) framework originally developed for glass-forming systems, suggest that experimentally accessible thermodynamic observables can become predictive of activation energies and kinetic timescales. These findings raise the possibility that certain membrane remodeling processes remain quantitatively linked to equilibrium membrane thermodynamics. This future-horizon article explores how such thermodynamic–kinetic correspondences might extend beyond interfacial lipid exchange to a broader range of membrane phenomena. We discuss experimental and theoretical opportunities for testing these ideas in systems including pore nucleation, domain growth, transbilayer transport, dewetting, and membrane asymmetry. Particular emphasis is placed on identifying which classes of membrane transformations may exhibit such thermodynamic–kinetic correspondences and under which conditions these descriptions are expected to remain valid. This perspective outlines a possible roadmap for assessing the scope and limitations of predictive thermodynamic descriptions of membrane remodeling processes and for determining when equilibrium thermodynamic properties can provide quantitative access to membrane kinetics.
The topology of π -conjugated carbon nanostructures strongly influences their electronic, magnetic, and spectral properties, thereby enabling applications in molecular electronics and spintronics. Graphene nanoribbons (GNRs), which are quasi-one-dimensional carbon systems, exhibit tunable electronic behavior. In GNRs, Clar’s goblet (CG) represents a non-Kekule open shell π -electron framework with a triplet ground state. These systems exhibit a zero HOMO–LUMO gap within the Hückel approximation, and thus, they exhibit a low-lying excited singlet state. Their open-shell structures with facile π -conjugated networks lend excitonic features to the network making them ideal candidates for spintronics. In this study, we derive generalized expressions for distance and degree-based descriptors for their network topology using double-weighted graph-theoretical techniques. In addition, Shannon’s entropies and graph energies are evaluated to contrast their relative order and energetics. Our computations demonstrate the existence of isentropic frameworks. Furthermore, quantitative structure–property relationships are determined for obtaining spectral graph energies through the topological indices, offering a technique to predict the graph spectral energies of larger networks without explicit computations of their graph spectra.
Thermodiffusion, or the Soret effect, designates a diffusive motion of particles driven by a temperature gradient, leading to a build-up of a concentration gradient. This effect is here measured in the liquid state on the eutectic alloy Ag_60Cu_40 , which shows negligible excess volume. No significant thermodiffusion was observed using both in situ X-ray radiography or ex situ energy-dispersive X-ray spectroscopy on separately solidified parts of the sample. This is in contrast to the significant Soret coefficients observed in molten Ag–Al and Al–Ni. Molecular dynamics simulations of thermodiffusion in liquid Ag–Cu [Sarder et al., Philos. Mag. 99, 468–491 (2019)] report significantly stronger thermodiffusion. However, the trend that thermodiffusion in liquid Ag–Cu is weaker than in other liquid alloys like Al–Ni is supported by our experiment.
Abstract Thermodiffusion, or the Soret effect, designates a diffusive motion of particles driven by a temperature gradient, leading to a build-up of a concentration gradient. This effect is here measured in the liquid state on the eutectic alloy $$\textrm{Ag}_{60}\textrm{Cu}_{40}$$ Ag 60 Cu 40 , which shows negligible excess volume. No significant thermodiffusion was observed using both in situ X-ray radiography or ex situ energy-dispersive X-ray spectroscopy on separately solidified parts of the sample. This is in contrast to the significant Soret coefficients observed in molten Ag–Al and Al–Ni. Molecular dynamics simulations of thermodiffusion in liquid Ag–Cu [Sarder et al., Philos. Mag. 99 , 468–491 (2019)] report significantly stronger thermodiffusion. However, the trend that thermodiffusion in liquid Ag–Cu is weaker than in other liquid alloys like Al–Ni is supported by our experiment.
