Thermodynamic features and environmental effects in a two-states molecular device under strict electrochemical control

The thermodynamic features of a synthetic molecular thread, recently proposed acting as an electrochemically-driven two-states molecular device, have been systematically investigated by means of nanoseconds time-scale classical molecular dynamics (MD) simulations and basic statistical mechanics relations. Results clearly suggest that the accessible conformational space of such a potential molecular switch shows a strong environmental dependence: the reversible molecular switching mechanism observed in liquid solution is effectively suppressed when the synthetic thread is hypothesized working in vacuo. Such a result has been related to a subtle energetic/entropic balance experienced by the whole system (solute and solvent) during the intramolecular conformational transition of the molecular thread, in presence and in absence of the solvent.