ABSTRACT
The intensive development of nanodevices acting as two-state systems has motivated the search for nanoscale molecular structures whose long-term conformational dynamics are similar to the dynamics of bistable mechanical systems such as Euler arches and Duffing oscillators. Collective synchrony in bistable dynamics of molecular-sized systems has attracted immense attention as a potential pathway to amplify the output signals of molecular nanodevices. Recently, pyridine-furan oligomers of helical shape that are a few nanometers in size and exhibit bistable dynamics similar to a Duffing oscillator have been identified through molecular dynamics simulations. In this article, we present the case of dynamical synchronization of these bistable systems. We show that two pyridine-furan springs connected by a rigid oligomeric bridge spontaneously synchronize vibrations and stochastic resonance enhances the synchronization effect.
ABSTRACT
There is growing interest in molecular structures that exhibit dynamics similar to bistable mechanical systems. These structures have the potential to be used as two-state operating units for various functional purposes. Particularly intriguing are the bistable systems that display spontaneous vibrations and stochastic resonance. Previously, via molecular dynamics simulations, it was discovered that short pyridine-furan springs in water, when subjected to stretching with power loads, exhibit the bistable dynamics of a Duffing oscillator. In this study, we extend these simulations to include short pyridine-pyrrole and pyridine-furan springs in a hydrophobic solvent. Our findings demonstrate that these systems also display the bistable dynamics, accompanied by spontaneous vibrations and stochastic resonance activated by thermal noise.
ABSTRACT
The desire to create nanometer-scale switching devices has motivated an active search for bistate macromolecular systems allowing for sharp conformational transitions in response to stimuli. Using full-atomic simulations, we found particular oligomers of thermosensitive polymers, themselves only a few nanometers in size, that possessed conformational bistability and reacted to power loads as nonlinear mechanical systems, termed "catastrophe machines". We established the bifurcation and hysteresis effects, spontaneous vibrations, and stochastic resonance for these oligomers. It is important to note that the spontaneous vibrations and stochastic resonance were activated by thermal fluctuations. Because of such mechanic-like characteristics, short oligomers are a promising platform for the design of nanodevices and molecular machines.
